I do not wear gloves when grooming summer or winter (then we do not get the extremes of cold you can get in places of the US)
The reason I do not wear gloves is because bare handed I can feel any heat changes, swellings or pimples.
As for being more hygienic, who the heck cares? The old saying "You have to eat a bushel of dirt before you die." Should ring true, I groom, will poo pick with my bare hands, trim sheep's feet, dag them (clip their dirty trousers) and because I am a distance from home, stop and eat a sandwich when I am hungry. The hygiene part comes in when I a) wipe my hands down my trousers in a vague attempt to clean them, b) assume that the purple spray I have used on their feet will somewhat sterilise the germs, c) when eating the sandwich I hold one end that throw that piece to the dogs.
I never have any tummy problems and only rarely do I get a cold and the only time I ever had the flu was when I was working in an office and not with horses.