Digital*ghost outlined some great ways to tally up the financial pros/cons.

Another idea if you choose to ditch the store is to sell your bulk lots even more in bulk, to save on insertion fees. You can combine 3 bulk lot sets of lipliner into one listing for $0.50, saving $1. Just times that by however many listing you generally have. People love bulk lots of things, so 9 instead of 3 may be a good way to save $1 per two listings and even generate more business.