I think jsmeeker made an excellent point. If the items in the mini-bar were comparably priced to what we'd see in a vending machine or in a convenience store (items are already overpriced in each of these places, so the hotel would still be making a nice profit), many of us wouldn't even think twice about using the mini-bar quite often. It certainly would be convenient. But when I'm getting charged several dollars for a snickers bar or $8 for a small jar of peanuts, I feel like the hotel is engaging in price gouging at my expense and it really sours my opinion of the hotel. If I felt the hotel had fair prices, it would change my opinion of that hotel dramatically for the better. I'd feel like the hotel was providing a true convenience, not just another way to siphon money out of my pocket.