I agree with Speedracer. Not all can go barefoot, unless you keep them on powder-puffs 24/7. I know farriers who do only barefoot trims for customers, no shoeing.......But when they take their own horses riding in a rocky area, they shoe them.
I've always told people my reasons for shoeing are "protection and correction". If they don't need protection or correction, just leave them barefoot.
If you live in a cold climate, this is the worst time to leave that mare barefoot. When that mud freezes, it'll be brutal on her feet