There is also the possibility that the tickets were given to the supervisor by the client and that the supervisor then handed them out to the 4 people on the team. I can see the supervisor not wanting to have to justify who got the tickets and telling the Friend to drop it.
I'm confused about Friend saying that this is not the first time that this has happened. It's not the first time that,
- She has been actively ignored by her coworkers?
- She has not been heard out by her supervisor?
- Her colleagues have been rewarded and she has not?
- Her colleagues have made a point of making plans together in her hearing and then pointed leaving her out?
Each of those problems has a solution, but not always the same one.
She should absolutely let go of not getting the tickets this time. In the future, if she is not rewarded, then I think she needs to have a converation with their supervisor about ways for her to improve her performance so that she might be eligible for these perks.
She should record the dates and times of the snubbings. A good supervisor should address this quickly, since it has the potention to turn into hostile work environment territory. Supervisor should have a word with the team that making plans to go out, when everyone who can hear them is not invited is rude and inappropriate for work time.