I can understand why designers hate it, because the industry becomes a race to the bottom, and devalues the profession by making it seem like a commodity. The same thing happened with professional photography, especially in the wedding photography segment.
But I don't have a lot of money to spend on design. I can mock a piece of crap myself, or pay what I can afford to someone willing to do the work (or in the case of a crowdsourced service, compete) for it.
A higher priced designer isn't really losing revenue from me, because I was never able to afford him/her in the first place - and at least a designer is getting some money from me.
Having said that, you do typically get what you pay for. For $300, you're typically not getting as well thought out a design as you would for $10,000.
You're likely to get a temporary logo that lasts you 6-12 months until you need a real logo. On the other end of the pricing extreme, Vancouver supposedly spent $239,000 on a logo design.
http://archive.citycaucus.com/2009/12/239000-dollars-for-gre...
Either way, they aren't my target market. My target market is the overlap of those who care and can afford to pay what I require. Outside of that, companies can do what they feel best for them.
* Annoying because it does promote cheap+fast design, which doesn't usually provide the desired results, and these companies may possibly devalue design even more.
There's always going to be people that don't understand the cost and importance of good design, and as much as I am continually put off when I hear business owners praising it, these are the types of people that would rather use WordArt for their logo if such a service didn't exist anyway, so there's not much to complain about.
I've also heard horror stories from both sides in the process, particularly when these cheapskates tend to be the ones who are the most nitpicky.
That really is the key point.
For a one or two person bootstrapped startup, a designer can be cost prohibitive, especially if there's not a lot of money in the bank.
For a sustainable multi-person company that's making money, they should really spend more money on a freelance designer vs going the crowdsourced route.
The companies that could afford to hire a designer but opt for something like 99designs are usually difficult/annoying customers, so in some respects, sites like 99designs are doing the higher end designers a favor.
In general, if I'm bootstrapping a project I'll start with a $5 logo from Fiverr just to give me something to throw up on a simple MVP. If it looks like the MVP is viable, I'll then spend $300 on 99designs. If six months have gone by and things STILL look viable, then I'm happy to pay a few grand for a "real" design.
99designs is still excellent for what it is.
The two people I knew that used the site as 'designers' were doing so as a means to dip their feet into graphic design. They were using it to see if they even had a chance in the industry. I'm not saying good design can't be had, but when you're competing with people that are putting zero experience behind their work and they beat you out on subjectivism alone, it leaves a sour taste in my mouth and gives the winner a false sense of accomplishment in the field. I'm looking at their logo design page right now, and it's a mess.
Not to mention the amount of times people have made money off of plagiarized logos, iStockphoto vectors or blatantly used Illustrator (worse, Photoshop) defaults.