Since the fees are advertised (though not included in the fare), I don't think you can say that the total cost isn't being disclosed. Anyone who has traveled since early 2008 is presumably factoring the baggage fees into the cost of their travel (as I do).

What's really irritating (to me) is passengers who are using advanced check-in so they can go directly to the gate -- with their oversize bag in tow. Once there, they are told they will have to gate check the bag but most airlines don't seem to be charging for gate checked bags. I don't care about the airlines losing the revenue, but I do care about the hold-ups and hassles it causes during boarding.