#1  I am sure a few people I have cut have badmouthed me and/or the theatre group. I don't worry too much about it. 

In my high school shows, I'm always conscious of the chorus and making sure that ensemble is strong. And yes, I also appreciate that more cast members means more butts in the seats, especially in high school. With that said, I set an upper limit on the cast in my head and don't cast more than that.

For example, this year we're doing Seussical, and I knew I wanted a fairly large chorus to thicken the singing. I also knew that our stage couldn't handle much more than thirty, so that was my limit. 28 auditioned, so I was able to cast everyone, but with 31, I would have had some tough decisions to make. With over 50? A lot easier to make cuts (as it is, I am finding my cast to be too large for some of the choreography).

The director of the CT who got me hooked on acting said something like this: not getting the part is just another aspect of the craft. If you really want to master the art of acting, you need to get good at handling getting cut.

In my experience, making the show artificially large just so nobody is cut is not the wisest idea. Our CT does a major musical every year with no cuts. This year was willy wonka, and had a cast of over 200. That meant at least 180 of them were in only one scene each. Yes, it fills the seats and makes us a ton of money, but the production budget then gets sucked into costuming oompa loompas and squirrels who are onstage literally once before curtain call.

Just make sure you're not cutting the same people all the time or casting the same people all the time, and your reputation should be fine.