Some people — mostly bra fitters — insist that an underwire in a bra is essential for any woman, even if she has small breasts. They make various arguments for this position, but I think that deep down it's a case of "I have to suffer with this damn wire digging into my ribs, and you should too."
Large-breasted women get to do cleavage and have to put up with the discomfort of underwires. Small-breasted women don't get to do cleavage, but we get to go without underwires if we want to.
And messenger bags. We get to wear messenger bags with cross-chest straps.
Hey, I believe in silver linings.