Can’t say that UV is usual in grow lamps, I personally haven’t seen many of them with UV, at least as far as home products go, just a few. I have heard that at industrial level they tend to use it more.
I guess the “good for plant growth” could be debatable, as UV is a natural part of sunlight it is good, but as far as I know it is rather dependant on the specific plant, because plants get different portions of radiation around the world, so some species really like it, but in other species UV causes them to start different defensive countermeasures. It can result in thicker leaves or excess resin on them etc. which for some cases could be a desired outcome, but for some not so much.
Don’t know if am I just in a debatable mood, but I would debate on the matter that UV is harmful to humans. It triggers vitamin D synthesis, which is rather important to us, but as it is with everything too much of everything is bad as it can damage and age our skin and eyes.