Great examples. So here is how I see each side evaluating these issues. Which one is right... That's a separate question.

Tithing. To an atheist, this just looks like a forfeiture of money: at best a waste and at worst the funding of a moocher. To a Christian or Jew (I believe that Islam also supports the notion of a tithe but I'm shaky there), they see God as the ultimate giver of everything and that 1/10th has two primary purposes: expression of gratitude and funding of the needs of the religion (buildings, etc.).

Sabbath observance. To an atheist, this looks like a wasted opportunity for riches via work. To a Christian or Jew, it is a literal commandment to follow the example of God and rest on the seventh day. Some point out psychological studies which point to the need of the body for a period of R&R which coincides with a weekly schedule. Personally, I think there's benefit to having that guaranteed day off every week so I can pursue my own interests. Working seven days a week is nuts.

certain clothing. I'm going to generalize this one because Muslims aren't the only ones who have particular clothing. Priests and nuns have their particular garments, as do Mormons and Orthodox Jews. Atheists view them as a restriction on fashion. Believers view them as a symbol of devotion or covenant - a constant reminder. A religionist could just as easily point out the cult of Nike or [insert fashion diva here] as a complete waste of money, too. Now I will admit that the full hijab is the most extreme, especially when they try to use it as an excuse to prevent law enforcement or identification. While I normally defend the right to worship what one chooses (or nothing at all), rights are always a delicate balance, but I don't believe that I should have to go out of my way (or have my tax dollars used) to cater to your beliefs. If you want to insist on hiding yourself, you get to pay for the additional law enforcement needed when identity verification becomes an issue.

not using condoms. This one is mostly a Catholic thing but it's not nearly as much about the condom as it is a belief that family is central to life. This one is as much about the general morality of sexuality as anything. An atheist views sex as primarily for pleasure and only secondarily as the means of promulgating the species. A religionist places priority on family and family creation first with the pleasure as a nice side benefit. It's all about priorities.

refusing medical treatment. This one to my knowledge is almost exclusively the Jehovah's Witnesses (as far as an actual sectarian teaching), but there are cliques among many religions. This one can also include reliance on herbal remedies, acupuncture, and chiropractors. In my opinion, each has a place, but it varies with the actual malady. I know some people who swear by a monthly session with their chiropractor. I have a co-worker who is constantly burning plant oils to stave off cold/flu. Are they irrational when it works for them? And there are those who rely too much on doctors and medicine as well (commonly called hypochondriacs) and whom the doctors are more than happy to keep seeing and prescribing to. To me, this is one where I think everyone likes to focus on the extremes where a middle ground provides plenty of room for sanity and rational thought.

diet restrictions. This one is prevalent in several religions, whether it be a permanent restriction (pork for Muslims and Jews, alcohol for Mormons) or a temporary one (Lent, Ramadan). The atheist simply looks at the presence of a restriction. The religionist looks at it as a warning against certain behavior.

Don't forget Yonaguni. It is something that is amazing, in that it is clear evidence of something going on. If built prior to the Younger Dryas impacts, then it would have been seaside property. From Nat Geo (and who doesn't respect them?):
Some experts believe that the structures could be all that's left of Mu, a fabled Pacific civilization rumored to have vanished beneath the waves.

http://news.nationalgeographic.com/ne...

That is if the original poster would give some reasonable stuff to begin with. Otherwise expect the unexpected comments to a post.

It is not the wellspring of all matter has attributes which are useful to rearrange into other forms than just atoms of the elements. There was matter before the first stars from existence came. However gravitating matter was produced, stars became of it and galaxies. Nucleosynthesis produced some other elements and some stars of a couple of generations exploded with the present generation creation along with the planets formed from the left overs. Then a certain range of planet types which had conditions where life might be able to exist, existed. There was a lot of stuff and conditions that needed to occur for life to exist.
I do not know how many such planets might exist in the about 160,000,000,000 light year diameter universe, but there are very roughly 100 billion galaxies of over 100 billion stars with a high percentage of them with planetary systems. That is about 10^22 stars and say that there is one suitable planet per 100 billion planet systems, that would still be 100 billion suitable planets. If the conditions of temperature, water, and perhaps clay exist, and due to the fact that Avogadro's number, 6.023 x 10^23 molecules per mole of substance is so large (that is why that little 50 mg tablet can have hundreds of thousands of molecules to treat each of the billions of cells in your body) there would be an almost certain creation of self reproducing molecules and things like hydrophobic lipids to form containers for other slop. Once life starts in not so hospitable conditions, then it is like a plague hard to stop as seen by bacteria living in very hostile environments on earth, such as miles under the sea floors, high in the atmosphere, in you highly acidic stomach and chemically active intestines, and even in pockets in granite.

Again, we kind of get to chicken and egg question. I think of the STNG finale where Q takes Picard to Earth and goes "Oh look, the goo didn't quite make it" and all ends, but for the intervention of three Enterprises...

It is mainly a Sci Fi concept, I am sure there are a lot more questions and issues beyond what you say, and I agree there is a lot to be questioned in such a circumstance.

And the space algae added some weight to the possibility...