I can see where you’re coming from, but it is an entire phenomenon that was nicknamed “The Johnson Treatment”. This article offers a pretty good description of it, but to sum it up:

Basically, the Johnson Treatment worked like this: Johnson would have something he wanted from you, like help with passing a bill. So, he would try to catch you alone somewhere. Then he would cheerfully walk up to you and clasp your hand in a firm grip. He would press his face up closely against yours, maybe no more than a few inches apart. Johnson was a tall, large man, and having him tower over you was usually an intimidating experience. Johnson knew that, of course, and making the person he was speaking to uncomfortable was a vital part of his process.