Since I wear 24/7 out of necessity, I don't have much of a choice. As Kensei said, it's that or wet/messy pants.
That being said, I really don't go out of my way to overly conceal the fact that I wear diapers. I'm sure that they're often poking out of my waistband or out from under my skirt when I bend over, but I'm not worried about other peoples opinions at all.
It's one thing if you have a humiliation fetish, but I just try not to spend half of my day worrying about whether the cashier at Trader Joes noticed my diaper.