I haven't seen one pro-Groupon (or general daily deals) analyses that says anything different than "it gets people in the door and generates buzz" which I think is nothing more than fuzzy PR talk since you very rarely hear of businesses that actually received long-term boosts. You read about how businesses don't benefit because mostly cheap non-returning users use Groupon deals (i.e. very few return customers) and it cheapens the businesses' full price pricing power to those who know of the Groupon (i.e. "since X was a Groupon in the past, I won't go there until there is a Groupon again").