You see it all the time in the NFL. Guys will throw a slap or punch at someone wearing a helmet. Most of the time fans just laugh because they know it won’t hurt or do anything even if the punch or slap is landed. They got a freaking helmet on. It’s not going to do anything.
Now do it to a player without a helmet on and its a different story.
It’s why baseball players even have an unwritten rule to take their helmet off before charging the mound. As much as the batter wants to destroy the pitcher, they want to at least create a fair fight.