There are some bloggers, and even entire sites, that are well known to play favorites. Even then, though - they're not getting special consideration from the vendors or manufacturers they advocate - at least, not directly. They might develop tighter inside lines to those companies and get the jump on pre-release demos and goodies.
I think it is a safer bet just not to play the "you're getting kickbacks" card with writers. You want to call them on a pattern of bias and personal preference and question their subjective credibility on a particular review or opinion? I think that is fine, and probably worth exploring. Calling them a shill or suggesting they're getting kickbacks is just "playing the Hitler card". It is lazy and almost certainly inaccurate. If you've got proof of it and there is *no* disclosure in the article, then you've got a major news story and the end of that writer's career.
See what I mean?
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