I tend to avoid them for the most part! Sometimes you can't though, and I have two children and to avoid crowds all the time would see them miss out. I am better if I am with them - they keep me grounded - and when I am in a crowd, I tend to stay near the fringes. With my son being on the spectrum, he isn't a big fan of them either, so my wife and my daughter often go off and do things together, which is fine by all of us.
I think it's important that a person doesn't avoid them altogether. There are times when you have to be in one, and if you have avoiding them for too long, it will give rise to a lot of anxiety. It's hard, though.