Whether they're charging for it or not isn't going to make development any quicker.
EDIT: I feel I should clarify.
The reason why the DDO store charging for something would not increase the speed of completion is because that's not how the developers get paid.
The developers don't get paid on commission, they get paid by the company. They get paid by the company whether they're working on something for VIP, Premium, or F2P. As such, charging for it wouldn't actually change a thing except make the playerbase angry, which would harm the company as a whole.