I signed up last month based solely on the dining as I don't really golf. I too assumed too good to be true, but then thinking about it, it probably doesn't cost them too much.
First, how many people are traveling to different cities often within the same month.
Second, its only two meals per month per location.
Third, how many people dine alone? Likely they will bring a guest along, and the clubs from my experience are way overpriced (not a complaint, just saying).
Finally, in almost all circumstances (New York being a possible exception) ClubCorp owns the club, so they're not reimbursing anybody the cost of the meals.
So far I've used it twice, and found it to be exactly as advertised. One other note - I believe if you sign up and cancel within a year they will charge a $250 cancellation fee.