Of course they can be addictive. But I say that as long as you are able to care for all of them adequately, can afford to keep getting them, and are not endangering your career/work life, then who cares. Get a bunch of holes in your ears and stuff.

My only concern would be... what happens when you run out of "regular" stuff to pierce? Move on to the crazy stuff, or just get really depressed? Neither sounds good to me.