bmo does have a prepaid credit card that you can get and all you do is transfer between the two accounts as far as i can remember its free. but you do have to apply for it just to verify u are u.
It really would be great if Public Mobile allowed payment through online banking/Interac online - for real not with an additional card - like most (if not all) other cell phone providers.
I have no interest in getting a Visa Debit card and considering that Public's parent company, TELUS, accepts payments through Interac Online, it's pretty absurd that Public doesn't.