Iwata said it himself, Pokemon Bank is for competitive players or obsessive collectors. It's not required, it's not pricey, and it's incredibly handy for said players... although, I really don't agree with Poke Transporter bein' a part of the deal. They should set aside some low-cost servers specifically for players that haven't bought Pokemon Bank or somethin'. No one's gonna be happy t' find a micro-transaction bein' required to bring their Pokes from past games to newer ones. Everyone should at least get a free trial for Bank 'n Transporter when first registering, as opposed t' just the first month the services are out.
Hell, they could probably of worked Transporter int' the new Dream World somehow. For free.