It won’t. If you are sitting somewhere and you are 6 feet away from someone its not an issue. At DS they have some food vendors without tables so they wanted to accommodate them so they allowed people to walk around and eat or drink. Think ice cream cone or Starbucks drink or Wetzels pretzel. They just asked people not to fully remove the face covering but pull it down, take a bite or sip and replace it. Very simple concept. What they are trying to avoid are people who grab a coffee at rope drop to hold, put their mask in their pocket and then walk around all day without it using the coffee as the excuse why. They won’t have CMs following people around, but it’s fairly easy to see someone walking for a long distance without the mask and without eating or drinking. For example, a CM at the carousel sees a guy turn the corner where Philharmagic is with no mask on holding a Starbucks cup. If he gets past the carousel without taking any sips the CM should step in and ask him to put the mask on. If you are sitting on a bench sipping on a bottle of water I doubt anyone will say anything.
You do realize that scenario is ridiculous, right? So Disney will have spotters with radios. “Human (you can’t assign a gender or skin color for obvious reasons) in red shirt and blue pants holding Coke cup didn’t take a drink for 15 paces in front of Peter Pan... GET HIM!”