I can afford it without problems, it's more the annoyance. I suppose you would say the same about taxes and fees the airlines tack on to their cheap advertised prices? If you have to know about the final price, you can't afford it?
Besides, from a report: "For instance, most states exempt groceries from the sales tax, others tax groceries at a limited rate, and still others tax groceries at the same rate as all other products. Some states exempt clothing or tax it at a reduced rate."
So yeah, having the price you have to pay in advertising and on the sticker would be great. Hell if I know what the local food or clothing tax is.