Yes ... this happens. But no it's not normal. Parents do not tell their friends and other parents from their teams about camps, leagues, training, out of club tournaments. Who knows why - probably to give their daughter a leg up.
When I played youth soccer our coach told every player and parents about every opportunity he heard of for extra play and arranged for us to do a couple things together. He wanted everyone on the team to get better - not just his daughter. It's not that way anymore
There are parents (one is particularly egregious) who take 1/2 of their club team and play in tournaments, camps, leagues, etc. and completely exclude the other girls on the team. No actually - its a group of parents. They're not playing in club sponsored activities so no one can actually stop them but you would think common decency would stop it. And they'd NEVER let that happen to their own children but that's the new normal. Worry about what benefits & advances your child and maybe a select few others . For all others - well too bad for them.
It will only get worse when your daughter gets to high school and the competition for things like looks from colleges/under armour, all american, and nike teams/write ups in the papers/spots on varsity & JV/ etc.
Use a forum like this to ask about certain camps. You'll probably get a better answer from anonymous parents on here who aren't worried about your kid outshining theirs
Ah yes, the "if everyone can't do it then no one should be able to do it" thought process. Does everyone on the team have to be friends all the time? It sounds like they are excluding some but not all. Maybe you can take the reins and your own time and efforts and organize a few things and someone will reciprocate for you.