As said, they do exist. I had always thought that the diapered retreat would be one of the best ways to meet/greet, and maybe put me much further in touch with my regressive side (which has been forced into the background by adult DL realities). I mean, if a person could go, and really regress for a week, or so, wouldn't that be the best vacation in the world??? The concept of $$$ always plays into it, though, and you'd never know if you were going to get your money's-worth, unless you participated, at which time it might be too late to get your money back, if things went awry, or it was hosted by con-artists / rip-off artists (of which the world is full of, especially in sexually-charged circles).
For the best bang, for your buck, it's probably still best to take control of it all, and go camping somewhere remote enough to enjoy, regress, and be safe from freeloaders. Even better if you can do that in small numbers, as in, a few special friends, out for the weekend, diapers & all.