> There was an additional checkout process to visit Catalina Island

Normally, I'm with you on this but isn't Catalina somewhat unusual as an airport?

I don't completely remember what the issues were from my tour, but I thought it was somewhat treacherous.

This is similar to people wanting to fly into Burning Man. They explicitly discourage it unless you have significant desert flying experience and even then they discourage quite a few of the lower powered planes. (Deserts can be particularly bad for generating enough lift.)