I see no problem with gifts at the discretion of management to (all) owners that amounts to a few pennies in MF/owner each year. This is an amenity to owners.
Rewarding "levels" of ownership is another case. Here, Marriott makes profits off point sales leading to the levels, with no direct benefit to the respective HOA or non-participating owners. Costs for such gifts should be borne by Marriott, not the HOA/owners.
This is what I think. Susan should get her celebratory wine because it's an occasion. Not because she has more points than someone else.