Sam's Club (and other warehouse clubs)

OK folks, let's have a frank discussion.  What's the deal with the popularity of Sam's Club and the like?  Full disclosure - I do not belong to a warehouse club.  I did shop at Sam's Club today, though, because they are having a Back To School Open House.  During this Open House they are allowing ANYONE to shop without the typical surcharge you'd pay for not being a member.
Granted, I am not your typical grocery shopper (I'll give you that).  I'm very educated on what a good price is, and know how to make a good price even better with coupons.  
I walked most of the aisles of Sam's Club and saw very few bargains.  The good prices were few and far between.  While the meat did look like really good quality - the prices were high.  Same with all the fruits and veggies.  Most of the items come in such large quantities that you'd think you're getting a great deal.  But if you think about it, and do the math - you can get a much better price (oz. per oz.) at the grocery store, and you don't have to buy in bulk to do it.
Of the few items I did buy, most of them were bought because I don't see them in the grocery store or because they were indeed a good price.  Usually it was because I can't get it anywhere else.
Do you belong to a warehouse club?  If so, what do you see as good buys?  Maybe I missed something.  I'm interested to hear your feedback.