Well, the problem is you're expecting a percentage based on the assumption that attraction for lolis is a minority; I have no idea what the percentage is, but the widely available content of loli-related material in multiple mediums (one of the most popular races in the MMO TERA, for instance, are lolis) suggests that if it is a minority, it definitely isn't a small one.
I don't really see the attraction, but it takes all kinds I suppose, and as fetishes go it seems innocuous while confined to media.