If the shot came from the
tee box on a 370 yard hole, I tip my cap.
A lot of it has to do with HOW the shot got there. If the ball lands in the center of the green, IMO this is unlikely an accident and I would be pretty upset. I would certainly stop putting and give my best glare
back toward the fairway. If however, the shot rolls up on the green, it may well be a career shot, hit a sprinkler head, etc. I would still stop what I was doing and look back, but could understand how this could happen.
How mad or aggravated I get is also based on the offending person's next move. An apology goes along way. If a "
player" (someone who understands the game and etiquette) ever did this by accident they would make every effort possible to catch up and say, I am sorry, I did not <put reason here>.......
Me personally, I would never touch the other ball. If someone does this to me and I feel it was intentional and they showed no remorse, I would let the ambassador know. If someone is
enough to hit into someone on purpose, there is no telling their reaction when provoked.