Great addition! Yes, a guide or a sitter or just a fallback person is always a good idea. Especially in new situations.
Wow, the camping festival! Gosh, how unaware people can be! I think folks who don't want to drink alone or smoke alone or be high alone feel self conscious about themselves and what they might do or say - and if you are sober, you will both see and remember. (In other words, they were not thinking of your or your mom or your feelings. They were busy thinking you might be judging them. As if it's all about them). So, yeah, fear of judgment. I agree. Also, maybe they do just want company, but that does not mean it has to be you, and thoughtful adults need to get that.
Good luck with the drug talk! Peace and Love!