I think one of the other reasons (or excuses, I guess) people use for jealousy is that they believe that art is all about talent, so you either have it, or you don't. And I don't think that's true at all. There's no such thing as talent. There is such a thing as people starting at a particular level that happens to be higher than most people's but that doesn't mean they don't have to work at it either; they simply just have a headstart.
Life drawings are a very valuable means of improvement in art. Perhaps people are subconsciously asking themselves why their image doesn't look nearly as good as it the things they're drawing, and maybe it just starts from there.
This is one of the things I often tell people. That getting better can sometimes be horrifying in strange ways. If you improve, it means your older pieces will look worse. At the time you drew them, they probably looked alright to you (and this process can sometimes take even a matter of half an hour or so), but when you get better, you also get better at noticing flaws in your own artwork. But that's true not just for your own art, but everyone else's. You might find at some point that you enjoyed someone else's work, and you thought it looked great. But if you come back a few years later, it might not look as impressive as you thought it was.
A converse exercise to the one you suggested is to buy works from an artist that you like particularly. And then keep improving and drawing and getting better. Eventually, you'll find the works you admire might not be as impressive as you thought they were.