So you sit around in the parking lot waiting for someone to drive up in an Escalade ?
Then you stalk them around the store to see if they buy lobster?
Then if you see them buy some lobster, you check with a clerk to make sure there isn't any left?
Then you stalk them to the register so you can see how they pay?
How else could you have seen several times someone drive up in an Escalade, then buy out all the lobster, and then pay for it in food stamps?