It's simply the act of being published that allows readers to say what they think of the author. Copyrights of any kind don't protect any published writer from readers having opinions. "Dissing" goes with the territory.
Honestly, I've yet to see a published author not encourage people to try and become as successful as they've been. I know overall traditionally published people look down on people who use self publishing as the easy way out, but frankly people who don't do their research have that coming. So I just have not seen someone actually say 'you suck because you're not published yet,' while I do see people say 'people who take money for art are icky.'
I've never met anyone who has said "People who take money for art art icky"; I have met people who say that making art only to get money is icky, or making art without trying to improve simply because you're successful is icky. I have seen people who think the type of art makes a person icky, especially if they are successful. And I have seen lots and lots of people (especially academic people, i.e. every art teacher I have ever had except maybe two) say that you should only make art for art's sake and if you don't, you are nothing better than an illustrator pandering to the public. I have heard people imply that if you are successful at doing one thing, and choose to continue doing that one thing because of your success rather than branching out and trying other things, then you are icky.
I am not saying published authors here, or on other writing sites I've belonged to in the past, or in college, or anywhere, have not encouraged people. But I am talking about how they treat others, how they say things, their attitude toward people who are just starting to write. I'm talking about people who treat having been published as if it entitles them to more respect or a better reputation, entitles them to expect everyone to just stop and listen to them, and in turn as if it entitles them to not have to listen to anyone else, especially people who have not been published.
So as to avoid any further drama here, I will use an example not from this site. I had a professor who was old and well-thought-of in the writing world, who was an honorary member of the faculty. He thought that because he was published and an honorary member of the faculty, he could just treat all of his coworkers in his department with disdain. He was awful. He'd snap at them in the hallways, talk about them behind their backs. He did the same with students he thought couldn't write. As soon as anyone asked him for an opinion, though, doesn't matter who you were or what he thought of you, he expected you to just bow down and bless him for taking the two minutes it took for him to tell you his thoughts. He expected you to follow them, too. If you didn't, he would lash out and complain about you and talk about you behind your back. (Luckily, I was on very good terms with him, but that doesn't mean it didn't bother me when I saw these sorts of things happen -- and they happened quite a lot.)
God, academics. I miss the debates, but not the ivory tower portion of it. Of course you can do art for art's sake; you've got another source of income! And, presumably, emotional release.
I have seen people essentially go with that blanket statement of 'ewww, money for art?!' and then furiously backpedal when they're asked 'what about the cases where the person is good enough to get paid for what they love?'
I can't say I have seen people expect more respect solely for being published, but in general the people who are published are the ones who've made a full-time commitment to writing and have been doing it for long enough to get money, and that's where they expect more respect. Definitely haven't seen the latter attitude of 'oh your opinion is worthless because you're not published,' likewise; it's 'your opinion without any sort of research behind it is worth less.' (And honestly, I used to think that selfpublished people were getting more rage than they deserved...and then I found a post dedicated to 'why trad pub sucks,' written by people who'd never managed to break into it.)
Oh yeah, there's people like that. Does that really have anything to do with the accomplishments and not the way the person handled being accomplished, though? I mean, if you start off 'gifted' (a polite way of saying 'smarter than average,' basically) you get set aside in a number of ways, and it bleeds over to the rest of your life. I've not had professors like that, either (fortunately!) but I have had some who don't tolerate idiots well, so come off as extra-intimidating.