People putting flyers under wipers don't have time to 'fiddle' or play silly buggers with bits of cars, and a piece of paper will hardly ruin the resale value. It's not as though there are menacing posses of flyer gangs lurking in dark alleys, waiting to damage your car. After all the idea is get people interested, not piss them off.
Standing outside clubs, while tolerated in more liberated parts of the world, will only get you thumped down here in ye olde one-seahorse town Durbs.