I grew up w/ Persians, shaving them is almost a requirement. Yes, even with regular groomings monthly and brushing daily. Our cats LOVED it. We did it around May each year so they would stay cool during the summer (but don't let them outside during the peak hours of the day for a week or so until their fur grows back a little because they could get sunburned). Any groomer can do this (and I believe most vets will too), but ask other owners who they recommend to find someone good.
We had a Great Pyrenees, and we decided to do the same thing to her and she would trot around the neighborhood showing off her haircut. I think all animals are different, some like it, some not. But it's not cruel.