Maybe they think he's a can of biscuit dough? Now, I squeeze Greg daily, because he is so squishy, but that doesn't mean other people can. They never ask permission, either, probably because "May I squeeze your baby?" sounds like a bad request.
At my doctor's appointment, one of the nurses stopped to admire him, then circled back and was going to squeeze. Brendan jumped in front of Greg and said "No! My baby, mine!" and scared her off. Thank you Brendan!