A lot of respondents are positive, if not ecstatic, about visiting markets/grocery stores, even super-markets in places foreign to them, but a lot of the comments seem to be focused on perusing and buying and food and snacks and things to take back home. I think they completely miss the point of the article, which is to interact with people. For that you have to be not driven by fear, as most Americans' ground state seems to be (I'm not talking about the foolhardy idiots who want to go backpacking in Afghanistan) and you have to be willing to speak the language, which is difficult for most Anglos.
Still, there are other ways to get out of your safety zone, not into danger, but certainly into discomfort. Go where it isn't just about buying stuff. Take local public transportation, visit the places people live, outskirts, suburbs, rural areas, take a hike, a country walk, visit local parks, farms, bookstores, book fairs, small temples, listen to people's suggestions ... be willing to not have an "efficient" experience.
Or, get lost!