the games are designed to be nudged, and literally EVERY good player nudges the game right up to the edge of tilting in competition. you aren't going to hurt the game unless you slam it around well beyond where the tilt sensor ought to be set anyway.
deciding that nudging is cheating is about like an NFL coach deciding that the forward pass is cheating. it's absolutely a part of the game and a necessary component of all successful competitors.
Quoted from TimeBandit:If you calculated the psi force exerted by the ball every time it hits something you would find an impact orders of magnitude higher than the forces imparted by energetic nudging, which causes a tilt.
well, a 200 pound person exerts roughly 1000 times as much total force on a pinball machine than a 0.15 pound steel ball (which contrary to popular myth, tops out around 6mph on a fast pinball playfield). yes the steel ball's point of impact is tiny, increasing the damage it can do to an individual plastic, but in terms of force applied to the overall game and specifically the leg bolts, it is not in the same ball park as a human being.
however, your broader point is correct that nudging a machine up to and including tilting will not damage it, because they are designed to be played in that manner. that's why games give tilt warnings. heck, some games even give additional tilt warnings as awards. it's absolutely part of the game.