I don't see any review content about this hotel at that link, only general impressions about entering Turkey as a tourist. Is there another article that clarifies the experience that the OP should have had?

The issue, for which my comments are accurate, is whether or not Marriott can force an international franchisee to follow certain hygiene standards when the local culture doesn't have the same focus or urgency, and the answer is they generally cannot, plus when traveling abroad and seeing health issues that are clearly a product of ignorance by other people, you need to speak up and call them out, rather than get upset and stew over it. Maybe other people are not as aggressive as me, and yes I do try speaking with a manager first to have the behavior addressed discreetly where possible, but when I see something as grievous as a jerk jamming their entire hand into a jar of cookies and digging around with their fingers (i.e. YYZ MLL), then yes, I start yelling. FT is chock full of reports of very upset people who witnessed something that they don't address on the spot, but then come back to complain about it. This is something that should have been addressed with the hotel, especially if what the OP witnessed is in contrast with the hotel's policies.