I guess some players follow "soft rules", and don't react as well when others don't follow. Running away in any striking mod (lenshu, boxshu) is a part of the strategy when you're leading in points, but people sometimes get annoyed. Other example is dm kicks or leggrab openers in ABD, some people can't counter them and it just ruins the fun for them, because they lose a casual game just because of an opener.

Next time when you encounter such behaviour make sure to right click the players name, and file a report in-game. If that doesn't work, just take a full screen screenshot of the situation, make a report via forums or just send it over on discord to any orange/blue/red name staff member : )