I do kind of feel like we've strayed from the path here, and I agree with you mentioning that earlier, but I'm going to say that you are incorrect as well, or some context needed, so I'm going to dip my oar in the water again. Sorry.
1) several of your colleagues aren't scammers and do ask for deposits. That's fine, and I agree with you. Once again you are a small group of fish in the pond and guys need to look out for more than just you and your friends. There will be scammers and there will be lost deposits. Ths has already been discussed. Also, whether they are swcammers or not doesn't really necessarily affect whether you should be paying deposits or not which is a different question.
2) I can't speak to how many people use their real phone numbers, but they're crazy if they do. None of the people I hang with use real numbers and all have a burner phone for all of their monger related activities. So, visit agencies at will if you like. I don't use agencies either, so it's all academic to me, but whatever applies to you.
3) Again I know that many MPs have cameras, although not all recording. Most indy MPs don't and so there's once again a decision to be made. This is in part why when I see MPs i generally prefer indies to salons although since I share no personal info I don't worry overly about it much even in the spas. It's a very small level of risk that I'm comfortable with and since I see indies or go to micros mostly it's unlikely to be an issue.