My dad, younger brother, and I all have the same name.

When dad died, he lived in Houston, and I lived in the British Virgin Islands. It was ultimately easier to convince AA to merge both accounts than it was to do the paperwork ordeal.

As for my brother, he's never cared about earning miles. No matter how many times I've told him it's worth it, he doesn't care. So until secure flight was implemented, whenever he'd fly, I'd get the miles.