To be fair, other companies are less, well... stupid. Today on SF Groupon, I see a climbing gym trying to get new people to come for their first lesson by offering 2/3 off. That makes a lot more sense along the lines of the gillette / dealer model (the first one is free).

I think a coffee shop, or really anything selling a commodity, is particularly ill suited to groupon type sales whereas a climbing gym, or really any business with probably a monopoly in a geographic area, is particularly well suited.