I feel like the total number of professional, adequately paid gaming writers in the world is rather low. And the ratio of professionals to hobby writers must be abysmal given that so many people are writing for free or for perks.
The economics of running/staffing a website are a much bigger part of this than has been discussed. If there were visible opportunities to become a respected, adequately compensated writer in the gaming media, I think it would naturally attract higher quality writers. But those positions are few and far between, so talented people are more likely to look elsewhere.
Having been a hobby writer myself, and eventually making it into the offices of one of the major U.S. websites as an intern and then a freelancer, personally I couldn't take it. The us-vs.-them mentality when it came to readers and competing sites was stupid. The fact that getting free stuff from companies caused writers to boast was ridiculous. I had my writing censored. To say nothing of all the inefficiency and wasted time, hiring of friends, etc.
Maybe the solution isn't just making sure paid writers are honest, it's about improving the self-respect of all those thousands of unpaid writers. Websites have access to this giant pool of enthusiasts who are willing to produce content with no regard for integrity or fair compensation, and not because they're bad people. They're just caught up in the excitement of being "part of the industry", at getting a peek behind the curtain, and being treated like they're special. If these people took themselves a little more seriously, if they were a little less willing to sacrifice their time and energy for a pat on the back, maybe the term "gaming journalist" would mean a little bit more.