Looks like businesses have collectively realised that groupon is a miserable deal and it's finally caught up with them, after having been running on fumes [1] for a couple years now. [1] http://blog.bodellconsulting.com/2013/03/01/groupon-a-bad-de...
Business owners really ought to know what their margins are. I feel bad for the ones who got pressured into bad deals, but they have to know what their literal bottom line is.
Even business owners that new their margins wouldn't know its value to their business without testing it in their actual circumstances.