Apparently they come from the factory "ready to install" but I didn't expect the package to be oozing brake fluid. Should I be annoyed or not? Seller seems irritated I'm even asking but It's literally everywhere. :-\
Maybe they didn't get as much fluid out as they thought. People would generally wipe them down at least I imagine. Were the pistons pushed back in? If not they weren't purged out. I would expect a little fluid though.
Annoyed? Yes, but there are degrees of annoyance. Myself, I would just remember that seller experience for future reference.
If as covered with brake fluid as I am imagining, a thorough cleaning along with compressed air blow-downs will be necessary. Just a normal wipe-down probably will not eliminate all traces of the brake fluid possibly leaving some to seep out on the next ride and possibly migrate to a painted surface.