Look, we're all human. We all belch and fart and use the restroom. We all sweat and sneeze and grow weird hairs and lumps and stuff. That's fine.
But if you need to blow your nose, go to the bathroom. And if for whatever reason you can't or don't want to, at least think of your server when determining what to do with that tattered snotrag. Don't just leave the slimy thing on the table--and don't throw it under the table, either. Would you do that at a friend's house? No? Then why is it okay in a restaurant? At least jam your tissue in your cup before you leave so your server doesn't have to touch it!
If you have a bunch of random crap in your purse to throw out, do it at home. Your table is not a landfill. Got one spare receipt? Sure, leave it on the table. No big deal. But we do not need your sucked on cough drops, your chewed on pen caps, your unused-but-unwrapped tampons or your empty Skoal can. Seriously people, just use your trash can at home.
And the issue that sparked this post: we are not a fucking nail salon. I have no desire to clean up your clipped-off nails. Don't leave your cheap plastic French tips all over the seat of your booth. Do you have any idea what sort of germs live under your nails? Gross.