According to the RBC cardholder agreement:
Even if you do not have Overdraft Protection, we may allow you to overdraw an Account or, if you have been approved for Overdraft Protection, we may allow you to exceed your approved Overdraft Limit from time to time at our complete discretion. But if we do, we may stop allowing you to do so at any time, without notice to you. We will not be liable for any loss, damage or inconvenience suffered by you if we stop
allowing you to overdraw an Account, in the first instance, or exceed your Overdraft Limit, in the second instance. (
https://www.rbcroyalbank.com/onlinebanking/servicech/pdf/PDA_Account_Disclosure_Booklet.pdf page 65 point 4b)
They're likely doing it to see if they can entice you to subscribe to their overdraft service (which costs $4/month + your $5 overdraft handing fee, from what I can interpret from their fee schedule at
http://www.rbcroyalbank.com/products/deposits/additional-services.html) or to upgrade your plan to a more expensive one.
BTW, a better plan to access "a few extra bucks to get you to payday) would be to put a few bucks in a separate account to draw on when you need it in emergencies... an emergency being you literally have no food in the house and payday's still 3 days away, and not that you want to go to the movies or buy a purse. Having a budget and sticking to it will likely eliminate the whole "ran out of money before payday" scenario. (Calculate how much you've paid in overdraft fees and the interest on that money the few times you've done it... now think of what you could have done with that money instead).