Do I hate part-timers? Not really...
I recently had someone drop me an email asking me about my seeming dislike of those freelance content writers who work on a part-time basis.
I write content on a full-time (far >40 hours per week) basis, and I state that outright in my marketing materials. I make a point of letting prospective clients know that writing is a serious, full-time endeavor for me.
Additionally, I have commented in the past that buyers are better off seeking full-time content pros instead of dealing with part-timers, hobbyists and others who may be willing to do a bit of writing.
Overall, I stand by that position. I don't, however, hate part-timers.
Here's the scoop... Overall, with all other things being equal, that a full-time freelance content writer is more likely to be reliable and to produce quality results than a part-timer. That's a general truth. After all, the full-timer has no choice but to get the job done and to do it to a client's satisfaction most of the time. If he or she doesn't, the cupboard goes bare in a hurry and the city stops by to turn off the water.
The part-timer or hobbyist may have a greater degree of flexibility--her or she might not, but you cannot be as sure that the work is truly important to him or her.
I also think that those who click keys all day every day tend to develop a higher level of skill, all things being equal. They also tend to pay more attention to industry trends, the changing landscape of online business and other factors that allow them to better meet customer needs.
Those are all general statements. And, as with all wide-scope rules, they are often proven inaccurate with respect to individual occurences. There are undoubtedly some occasional writers who are particularly gifted and can do a great job. Their skills may allow them to outperform a full-timer who isn't as talented.
Overall, I think my perspective is probably right and personal experience with part-timers has generally been consistent with it. However, there are exceptions and I recognize that.
So, I don't hate part-timers. If someone can stumble onto the right one, it can be a winning situation. In general, however, as a buyer I would opt for a full time freelance content writer whenever I had the chance.