I try to take a positive outlook on things like sidepipes, I tend to think that the majority of people are smarter then the sidepipes and know that they are part of the exhaust and as such are hot and can cause burns!!!! Heck, so can a hot tailpipe!
As for kids burning themselves on them, lets place the responsibility where it really lies----Where the heck are these kids parents and why are they letting them run around loose and messing with other people's cars anyway??? Yeah, it's a shame if they get burned on them but IMO it's certainly not the guy's fault who owns the sidepipes!!!!! I've had a number of roadsters, cars, coupes, and cruizer's with sidepipes or lake pipes, along with a number of Harley's with drag pipes and been burnt/seen others get burnt by them. I'll more then likely run them again, too. I like the looks and like the sound, plus on some of my really low to the ground creations it clears up a ground clearance issue!!!!
I don't think we should have to build our cars so that they are idiot proof, not sure it could be done anyway! If the sidepipes are in a place where they are a risk for a leg burn every time I get out of the car I usually run a stainless heat shield over them, the laser cut shop here in town can cut some really nice designs or even script writing into them!
Common sense just isn't really all that common anymore, is it?