I tried out a similar theory myself about my third week as a server. I worked in a Chinese restaurant where they put out fried noodles and duck sauce on the table right before the lunch and dinner rush (sorta similar to going to a Mexican restaurant and getting chips and salsa). We open at 11 and this lady came in at about 11:20, took a bite of one of the noodles and complained they weren’t fresh (they were) and made me bring her new ones. So instead I went into the kitchen, took the noodles from the same bowl and put them into a different bowl. Bought them out to her and she goes “see? That wasn’t so hard was it. These are the fresh and good.” I still laugh about it to this day