If you are looking for the epitome of barefoot-friendly, the DeCordova Museum, a lovely contemporary art museum in the Boston suburbs (Lincoln, MA) is it. I went there on a whim today, a perfect early summer day in the 70s. I spent two or three hours wandering around their sculpture garden looking at the (very diverse) installations and statues. The sculpture garden is part grassy, part forested, all beautiful and great for the feet. What a feeling. (Well, there was a bit of gravel here and there.) I stopped for a while to do some reading on my iPad, and then entered the museum buildiing, still barefoot. Inside the museum, which was not crowded but had other visitors, literally no one cared. Most rooms had a guard on duty, all in their twenties or thirties, Not one of them gave me a second glance. (I even used the bathroom, which was spotlessly clean.) Spent some more time sitting on their sculpture balcony, admiring the view and reading the news. There were some other people around, but it was as if barefoot in an art museum were the norm. No one gave me a special smile or a special glare, no one called the cops, no one asked me where my shoes were. Literally no one cared. Life as it should be.
The Boston museum of art is fabulous!.......but I wasn’t a barefooter when I went to the Rembrandt exhibit there.