I live next to a really popular rail-trail here and was out walking my dog when I heard some arguing up ahead. My older neighbor was out walking on the path and was into an argument with a roadie that was cruising down the trail at 20mph. My neighbor had yelled at the guy to slow down and an argument ensued.
I stepped in to break up the argument (before it went to fisticuffs) and try and let cooler heads prevail. I tried to explain to my neighbor that the bike has every right to be there and I tried to explain to the cyclist from out of town that this is a family trail full of kids and moms on bikes, rollerbladers, dog walkers, etc. and if he wants to ride that fast he should be on the road. FYI, there are no shortage of great cycling routes right in the area we were.
Anyways, all the guy would say is that he had every right to be there and he could ride as fast as he wanted. I told him he gave a bad name to cyclists everywhere with his attitude and that I wouldn't be surprised if he got his ass kicked by locals.
People like this give us a bad name. Try to set them straight if you run into one.