I'm not an ATV hater- in fact I find them to be very useful vehicles, and I wouldn't turn one down if someone offered it to me. However, like many things irresponsible users can cause problems. Also, like many things, there are appropriate places for them. Important habitats for sensitive species at risk are not among them, in my opinion.
And generally, my philosophy is that these vehicles (and all other fossil fuel powered machines) should be tools, not toys. Use them for an appropriate purpose, not just to drive around in circles for fun, IMO.