Frankly, the appeal of Gacha is the same as the appeal of regular gambling. It's the idea/thought that "just one more try" will win you the big prize, or the item you really want. Gambling, however, can turn into a serious addiction. With Gacha, I really hope people aren't seriously addicted, because I'd tell them to go to Vegas or something instead, since then at least you could be winning real money instead of a bunch of pixels.
Makokun ~ Dark Lord
Proud Member of Shin-Ra