I'd do that stuff in a heart beat if it was a controlled environment (ex: got permission, proper safety gear) but not the way some of these guys do it. Some of these guys don't have such protection, and I would not have the balls to do that. Only takes one slip... not to mention I'd be worrying about getting caught the whole time so it would distract me. I guess that's part of the thrill they're going for though.
Though what I would prefer is more vertical climbing like cell towers. I'd do that in a heart beat given the chance. The view from up one of those would be amazing and it's fairly easy climbing compared to stuff not meant to be climbed on.