I tried doing it once when I saw a video of a person do it. Yeah... It hurt... Didn't like it... Haven't done it again. And I do think its bit rough on the machines, so I wouldn't do it again even if it didn't hurt, out of respect for the operators.

But, at Galloping Ghost. One time Black Knight during extra time I had 2 balls stuck in the shooter lane after the game. I couldn't plunge them regularly. I told the employee and he did the smack plunge to clear it, and it worked. But, again he's an employee. I wouldn't want to get yelled at for doing something like that. I have too much fun at GG.

Yeah. I think you are correct. But, nothing wrong with the old school method of using the plunger.
Also, from all the pushups and weightlifting and dips. My wrists have been basically shot and useless. I had to scale back my bench press and limit my reps because doing a full extension was really hurting them. And I'm not going to lift without a full extension.
After easing back on the dips and pushups. Most of the pain has gone away. But, it can flair up from time to time.