I feel like I don't really know enough about this to speculate. I think both articles (this one and the one it links to which argues the opposite) both have some good points. But I get the impression that, like me, neither author really knows this space well enough to draw good conclusions.
I like the data point (from the baptiste piece) that offline commerce is still 95% of spending, thus it is a 19x larger market than e-commerce. I think the point in the shah piece about "I didn't even want a pastry" is also good. But to me it doesn't really argue that this is a failure. To me, it argues that this is a first step which, like all first steps, will need to be followed up with refinement of their monetization strategy.
I have a certificate in GIS. I live without a car and have some other issues. I have been thinking here lately about my frustrations with using the internet to try to find stuff in the real world. In many ways, the internet has been a godsend in that regard. But in other ways it has been pretty crazymaking. I asked a bit about this elsewhere recently. It didn't really result in some huge epiphany that I am just doing it wrong. It resulted in me concluding that this intersection of the web and the real world is just not that well done yet.
So I think Four Square is breaking new ground. Yes, that's always risky. But I am guessing they understand this space better than the hn equivalent of a few "armchair politicians" looking on from the outside. (My dad had a brilliant solution for every social ill ever. And was happy to share his wisdom while watching game shows and eating peanuts and doing not a damn thing about any of them. So, erm, I learned long ago that "talk is cheap.")