It's all  here

Y'know, that's not entirely insane.  

As long as you put a towel, or anything else that's equivalent to clothing, between your ass and the seat, and you keep something similar between your genitalia and the table on which my food's being served, ain't nobody's business if you do.  Don't wanna see, don't look.

Y'all take responsibility for not directly applying dead cells from your wabbily bits (tm) onto my seating and eating surfaces, and I take responsibility for keeping the photons that bounce off your body from hitting the back of my retina.  

Whether someone wants to wear clothes or not is his problem.  The light that enters my retina is my problem.  Seats and the restaurant tables are everyone's problem, and figuring out how to deal with any conflicting interests without violating anyone's rights in the process is why government was invented in the first place.  We outsource the annoying stuff to legislators and lawyers because a million individual instances of fisticuffs is a crappy (and thoroughly non-scalable) way to solve differences of opinion.

^ Remember Hitchhiker's Guide:

Don't panic and always know where your towel is!
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