Alwaysbehind, thanks, my point exactly.
My2Geldings - I'm not disagreeing with your point that she shouldn't be out there working her horses. I am saying, however, that those horses are her responsibility. When she is unable to work them herself, she needs to either find someone who will do it for free, find someone she can barter with to do it, find someone whom she can pay to do it, or pay the barn owner to work them for her. You should never expect the barn owner to provide complete care and full service unless that's what you're paying for, and it doesn't sound like that's what she's paying for. (Otherwise, the BO probably would have just worked the horses without asking.)
Just as an example, take a look at this farm close to us: Untitled Document
Notice where it say part way down - "Additional Services - service fee will be added to monthly board: body clipping, basic clipping, mane pulling, hand walking, poulticing, hosing, icing, wrapping legs, lunging". That's all in addition to the normal full board rates. Another one... Boarding and Leasing at Green Acres Equestrian Center
Notice the last bullet point - "Other services, such as grooming and exercising are available". That's in addition to full board at $600 a month.
If you sent your kids off to boarding school, you'd still be responsible for them if they broke anything or were rude and disorderly. Same thing with horses. If you're not paying for complete and full service, don't expect the barn owner to provide it for free.