Same way it's fair that monsters can knock you out of events/interactions due to being "under attack" - It's an intended part of the system. You can't control people harassing others because every time SE tries, people try to fight against the changes they make.
Difference is, when this happens you almost always can just immediately click and try it again.

Again, if this happens to you on an unspoiled/mooch, you have just lost a whole lot of time.

Happened once? No big deal. Same person doing it to you multiple times? Report for harassment.
With me, it hasn't actually been the same person doing it. It still happens extremely frequently, which is exactly why I made this thread. This is one of the biggest recurring issues for me that is getting me irked at other players, and like I said there is no reason for it to exist at all especially when it can potentially serve as such an easy means to grief other players.