Its ok to spray horses in the face IF they like it/are used to it/want it. Preferably with mist like spray. Some horses will not like it.
Ditto that. I've washed two horses who just love being sprayed in the face. We put the hose on the mister setting and let it fall down on their face: they love it! But a lot of horses don't; so, know your horse ;)
Being sprayed in the face is disrespectful and/or some horses just don't like it so owners don't?
I find most horses when initially introduced to a hose don't like being sprayed anywhere. Desensitize them to being sprayed (gently) in the face just like one would get them used to being hosed on any other part of their body and they learn to tolerate and even enjoy it.
A good way to introduce the idea of having the face hosed is to mist the area above the head so the water falls down like rain. I alternate between that and actually spraying the face in order to avert a total horsey meltdown.
I just held gypsy and sprayed the top of her forehead so the water ran down until she stopped moving and put her head down. Down when I have the hose she will step forward and put her head down for me to spray.
Yes sometimes it gets in her ears and she gets mad=]