"Being told what's acceptable and what's not." Well, it is their site and they would be the ones liable for any lawsuits. I can understand the site being apprehensive about some things. The strange thing though is that you said you set it up for 18+ and most places around the globe that's the legal age to smoke.
I mostly use Facebook as a way to stay up on my favorite brands, musicians, and sports teams. It's nice getting notices of new products, discounts, and concert or album release dates. I also play a few games on there, yes I've been playing Candy Crush for almost a year now lol, and do use it to chat and share photos with friends and family who are scattered all over the country.
I've never understood Twitter. Limiting one to 150 characters. Doesn't make sense to me. I do have an account, but like Facebook it's mostly to follow sports teams or stores I like for new products or deals being run. I hardly ever tweet. I do love my handle though, an old high school nickname hoctorthelovedr .
Youtube is definitely where it's at as far as the pipe world goes. There are a number of pipe channels with over 500 followers. A lot of information on what's new, what's trending, and events.