Probably because people think it takes away from real human artist. The fear they'll be replaced and wont make any money off it because some artist use art to make a living. Unfortunately not everyone has the means to afford the artist. But I feel as long as artist use them as a reference, a tool per say, I don't see the issue is with them. It's no different then an artist using a reference to make something of their own. Art comes from somewhere one way or another. Sometimes artist has to use a reference to better visualize what they want and that's ok as long as they make their own. No different then what AI is doing or what it could be used for. So I agree with you, I don't see the problem. A lot of people blow it out of proportion.