No. I recently made a reservation online using Choice points for an upcoming stay in Comfort Inn & Suites Downtown in Chicago. I was confirmed without any question about credit card ever being asked. I am very aware of this, as this was during a time I was trying meet spend requirements on a couple cards, and wasn't sure which card I would want to be using by the time of that stay. But I didn't have to choose which card to confim with, since I didn't have to give any credit card number.

And this is the guarantee policy on my reservation:
It's clearly saying that it's my points, not my money, that I'll forfeit if I don't cancel in time.

Now, I don't remember if that's the case when booking Choice Scandinavian properties, I don't remember if that's the case when booking with Choice points over the phone, and I don't remember whether that's always been the case with Choice points reservations booked online. But it's certainly the case right now with Choice redemptions within the US at least.