Accumulated Marriott points can be redeemed for dining discounts, not for buffets.

The most conventional way to earn Marriott points is to accumulate them from your stay. With the exception of the Genjuku, ResidenceInn, and TownePlace Suites hotels, where you get 5 points for every $1 spent, the general ratio for getting points is 10 points for every $1 spent, with a few others at a 1:2.5 ratio.