I don´t get why they make a fuss as if points are money. They aren´t. Points are only useful in KOG, and since KOG is a once-in-history-event, the only reason for not spending would be if they are confident that they won´t need any cards. Which they can´t because they don´t even know how importnt the cards are gonna be. And since the MC is buying as many cards as possible, cards seem to be very important.
@DonGiovanni I guess his plan is to be the top player in this round as well and get a lot of new points. After all, the most important thing is not getting many points, it´s surviving all rounds. And for all we know, the cards may be usable in later rounds or he might have the opportunity to trade them back after finishing the round.