This is a very interesting discussion, it's nice to see all these different views.
-If- we were to charge extra for BBC, I'm wondering if people would complain about it. I don't honestly think I'd feel good if I joined a martial arts school for $X/month, then find out if I want the 'complete package' it'd cost $X+$Y/month. But I'm betting this is just because I've been a part of it where it is free.
Now that I think about it, from a business perspective, I bet most people would just accept the extra cost as how the business works.
To go along with the discussion though, I don't know if I see it as unfair. Some of the local gyms offer an introductory price with restricted hours, and it limits the number of times you can come a week. For more a month, you can come anytime and as much as you want. And while there are people there to help you, it'll cost even more a month for personal training.