It's just like most hobbies out there -- there may not be a practical use for something, but if someone enjoys doing it, then why not do it (as long as you're not breaking the law or stepping over other's rights). Hell, what's practical about flying model aircrafts... Nothing... but it's fun and enjoyable, so people do it.
Some people would say that me having over 700hp in the car I drive to work is impractical, but does that mean I shouldn't have it? :?: I take it to the track on the weekends and have a blast with it and I'd hate for someone to make a law that didn't allow me to enjoy all that power.
With both shooting guns and racing cars, there is a right way and a wrong way to do it.... and with both, doing it the wrong way can become very deadly.