We definitely agree that the market for daily deals is over-saturated, and there will be tons of failures/exits (see Facebook, Yelp). That said, the doesn't really change the calculations for small businesses. They are either being helped by the current structure of daily deals or they aren't.
It is obvious that the model needs to be tweaked if these companies actually want to help local businesses. Things like Groupon Now are trying to do that, but the factors we discuss in this post hopefully lay out what small businesses need to be thinking about before they sign up for deal. Opportunity cost is a real cost.