First, what absolute savage would take a new acquaintance or romantic interest grocery shopping and make a show out of leaving the cart? Thats absolutely a red flag.

Second, you are right that with strangers it won't matter if you judge them, but thats only true from their perspective. The way you think and carry on affects how you feel, its not a good idea to waste energy judging people in that way. It affects how you perceive and interact with the world essentially.