Amount of tip

I am a customer and was wondering can the shopper see how much I tip? I am so happy to have someone shop for me because I am disabled somewhat that I most likely over tips anyway I get the same shopper 5 out of 6 times a month. How is that possible? He couldn't be sitting in the Kroger lot every day when I place my order. I usually order on Thursday and Friday. It's just odd. OK that was a couple of questions. Thanks in advance for any answers.