Watching buildings implode is human catnip. If you've got nothing better to do on a Summer afternoon then you might as well head down to a local street corner and watch something get blown up (or in). It's like watching a Michael Bay movie with more of a plot.
Normally there aren't any risks, or there shouldn't be -- but one man in the Czech Republic found out that hard way just how dangerous an implosion can be. Seriously, the rock flying makes this terrifying.