I think there are three ways to handle this properly:

1. If you know it's gonna be busy do not go there.
2. If you must go there because you have something more important to do there than the rest of the crowd (e. g. tourists in your home city) you may complain all you want.
3. If you go there, and there is a crowd, and they are all there for the same reason you are, you can talk, but not complain about it. You can't complain about people who all you know about is that they are behaving the same as you in a certain situation. That's like complaining about yourself. That's saying there are many people here, but you are not part of the people.