Some men never grown up*. Growing old is not the same thing as growing up.
I shudder to think of this as amusing, if this happened at any other age, it would not be regarded as funny.

In elementary school, the kids would get yelled at, sent to the Principal's office, there might be detentions, or extra homework.

In high school they'd likely be charged with assault and brought up on charges, at the very least they'd be expelled and ordered to counseling and community service to make ammends. Unless they were star players on the school sports team, then it'd be hushed over, and their wrists would be slapped.

In adults it would be considered assault for sure. Lawyers would be involved. Restraining orders, perhaps. Eyes would roll at the stupidity of it all. But because of the stereotyping of senior citizens as passive people with no personality, this is regarded in the media as something to be applauded and even laughed at?
Grrrrrrrrrrrrr.
Sigh.

Okay, I'll step off my soapbox. Y'all go have your fun.

* I'm not saying my gender is immune to this, it just generally does not result in fisticuffs in most instances.