Is there any particular reason the band hasn't released anything besides studio albums or compilations?
The fans are hungry for more. Things like live albums (Unplugged, Storytellers, House of Blues, etc.), unreleased songs, unreleased footage (SLDD Doc), and other stuff like that. If the reason is a potential sales issue, then why not use the official website to do smaller limited issues, maybe based solely on pre-orders or a store exclusive (like Best Buy) or something like that.