I took advantage of this as well. I ordered 5 GC for $5.00 on Wednesday. We used our first one yesterday. Our total came to $52.xx + $8.xx added gratuity, and we paid $32.xx for our meals.
I look at these as a way to try new and possibly more expensive places than you normally would as opposed to actually saving money. Our bill was so high because we each had a seafood dish (and fried pickles
)