Oh, so money. I've got an idea. Make it so that you get discounts on hats/items in the town and maybe sell semi-exclusive hats/items, items being things other than hats, like boots. You could make a formula for the price where the range has a minimum price, maximum price, and some function that determines where within the range of minimum and maximum price that falls based on the total number of hours towered with the past however many weeks, days, hours, or like some threshold number of hours for a particular set of hats/items.

Hell, you could even get rid of the max price constraint. It doesn't have to be a discount. Let's say you made it so players could show off how many gralats they spent on a hat, you could sell people that want to flaunt both their guild prowess and gralat wealth a more expensive hat that you could only pay that much for if your guild was kicking ass on the tower and you had a stupid amount of gralats.

This kind of started off with my mind going on a tangent about wishing guild towns would somehow be brought back.