After all this time, since they changed it from items to points (which is wayyy better, because I don't need to waste points on items I don't want to get to the item I actually am after), I am still at a loss:

How many CSC do I have to buy to fill up a loyalty card? 5 x 1k for small stamps plus 5 x 2k for large stamps, 15k? Can it really be that much?!?

I wished it would simply say so on the reward card page :-(

Nono, it's just 1k per stamp. The way they worded is strange, but they just mean that after 2k total buys, you get the large stamp. Like, buy 1k, get small stamp. Buy another 1k (so 2k in total), get large stamp. So 10k CSC in total, or 100$, in total per card.

Thank you so much!