Citing his town's sparse population and an increasingly niche comic-book market, Edge Comics owner Chris Moore admitted Thursday that he is not really sure how his store has remained in business for the past seven years. 'With my storefront rent at $3,600 per month and inventory running another $1,500 on top of that, I really should have been out on the street years ago,' said Moore, adding that even on a good day he sees no more than 20 customers, tops. 'I mean, I'm not exactly selling luxury cars here. My main customer base is 12-year-old kids who stop by once a week to spend their allowance on a $3.99 comic book. Or two comic books, if I'm lucky.' At press time, the store's lone customer flipped through a collected edition of Punisher MAX before putting it back on the rack and quietly walking out the door. 