I tried to answer some of your questions, they are bolded
I've tried to add a little on as well.
Thank you both for your patient explanations. The whole DVC thing seems like it can be very worthwhile for a person (or family) who takes the time to evaluate their travel habits, works through the math, and understands what they're getting into. Adam's on-camera persona does not instill confidence that he would approach it with such a logical mind. Still, I think that
he thinks that he's being clever by prepaying for his vacations... or business ventures... the line is a little blurry for his life (just like his video footage).
As for whether Adam truly has social anxiety, who knows? It's certainly a convenient excuse if he's a jerk to his fans in public, and with the rise of "geek culture" recently, some level of social awkwardness is seen as way more hip than it's ever been.
Just from watching his videos, I've always thought that he seems happier when he's around others. He just seems to have more energy and a better disposition when he has someone to bounce off of. That can be deceiving, though. Personally I am pretty introverted and prefer to be by myself or with the company of only a few close friends or family members. But I can fake it like nobody's business! For a short while where needed, I can put on the act and interact with tons of people at dinner parties, networking events, and other such social situations. If you'd met me at such an event for the first time, you could easily make the mistake that I am an extrovert who loves such situations when in reality it couldn't be further from the truth -- I find them to be nerve-racking, exhausting, and at times even panic-inducing.
On the one hand, maybe Adam really does suffer from some level of social anxiety and is just good at hiding it in his videos. On the other hand, it's no excuse for him to be a dick to his fans (the people who literally pay his bills), and hiding behind a self-diagnosis is a chickenshit move.