I know a few TMs at my store would get ticked whenever someone new was hired because:
a) they would have to train this new TM (uh, it's part of your job folks) &
b) they would see their hours cut while the newb got more hours (it's called "learning by immersion" - once they're comfortable in role, their hours go down).
It may not be the sole reason but could be a small piece of the puzzle.
Honestly, Target is a LOT like high school with cliques, popular well-liked TMs, the unknowns, the power players, the nerds, etc.
Sounds like your coworkers are still in that rut.
A tactic: Next time she rolls her eyes, just say "I know it bugs you whenever I ask you anything but it's only because you've been here longer & you know what to do. I'm just trying to learn how to do things the RIGHT WAY & figured YOU were the person to ask."