Work holiday parties that exclude some employees?

Has anyone else ever experienced this? I am feeling so sad for my husband. His coworker told him that he found out that there was an employee holiday party after the new year that only some employees were invited to. The people in attendance at the party were all given an additional bonus and there were really fancy giveaways. This wasn’t like a party at a coworker’s house, this was put on by the company owner and HR, but only some people were invited. My husband constantly goes the extra mile, staying late and working weekends, and is well respected at work (as far as he knew before finding out about this.) I think his spirit is really broken and he’s going to go into quiet quitting mode after learning about this. Just wondering if this is something that is considered normal at companies? I definitely thought that something like this would be a no no.