Your Canadian-ness is showing, LOL.
Many Americans (particularly older folks from the South) have associations with being shoeless that are class-specific, and an etiquette background that says it is rude and overly casual to appear with your shoes off in front of anyone outside your household. My MIL was really poor in childhood, as in, didn't-wear-shoes-at-all-in-summer-because-kids-outgrow-them-and-that's-too-expensive. Once she reached adulthood you could not pry the shoes off her in public if you used a crowbar, and seeing unshod adult feet made her cringe. (She didn't like unshod babies, either, she was forever buying shoes for our kids when they were too young to even crawl.) My BIL married someone from a no-shoes-in-the-house background, and they were locked in a passive-aggressive war over it until the day MIL died; she really did not like people taking off shoes in her home, but SIL did it every time she stepped over MIL's threshhold, and so did BIL, because his wife had him trained.
I grew up mostly in the Deep South in a family that could afford shoes, but we kids generally didn't wear them in summer -- except if guests were in the house, because going without shoes in front of guests was considered rude. I actually own very few socks and almost never wear them, but I never go sock-footed because my balance is wonky and I'm apt to fall on my face that way. If you force me to remove my shoes and don't give me a warning or loan me non-slip house slippers, then you're getting my bare feet.