Conway, South Carolina, US
I've always been under the impression that BTTI was Hanson's individual spin on doing a Rock Boat type event. I've never been myself, but from what I've heard TRB very much caters to repeaters. I.E. the more times you've been, the earlier you get to book, the better room selection you get, and they get exclusive merch too. Basically, Hanson and Island Gigs didn't invent this method of booking and it's obviously worked well for other events. The concept of cultivating "brand loyalty" is a huge thing in the retail/sales world, which means giving the best perks to the customers that consistently spend the most money to try to make sure they're always choosing to spend that money on your brand vs. another one. Maybe BTTI is in high enough demand right now that they can afford not to offer any extra perks if they chose not to, but that might not always be the case and it makes business sense to build a solid repeat customer base while they can. Like Paola said, there are always rooms left for general sale, and at least with the Melia, the rooms left at the end have been the cheapest ones, so it's not even a matter of it being unfair because new attendees are left with the most expensive rooms. I might be spoiled as a repeater, but I can't imagine choosing not to go because a room type sold out unless I just plain couldn't afford what was left. All of the rooms are nice.
I also agree that I would enjoy it less if they made it bigger and let it be 3 people to a room. A big part of the appeal to me is how laid back and intimate everything is, and increasing the crowd size by a third would make it that much harder to see in the the crowd, that much longer of a M&G line, and that much harder to have a fair chance to participate in whatever events are happening.