I call them out on it: “WTF is that? You trying to prove something, tough guy?” And that’s the end of any chance of working with me, selling something to me, intimidating me, or anything else. You’re just a dickhead, and I WANT you to know that’s exactly what I think of you. Thanks for letting me know you’re an asshole from the start, saves me a lot of trouble.

A good firm squeeze and release is all that is required, and any reasonable person understands that.