Question for people who claim thong swimsuits are inappropriate in public because they show the butt cheeks, where do you draw the line?

Because pretty much all bikini bottoms show at least part of the butt cheeks.
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+1 y
So how do people justify saying certain ones are inappropriate and others aren't?
Question for people who claim thong swimsuits are inappropriate in public because they show the butt cheeks, where do you draw the line?
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