You are quite correct that there aren't enough categories for U.S. sellers. Many of us have asked for new categories because we can't find suitable ones. I also wish they would be added sooner. I do the best I can with what is available and don't waste my time policing other people's listings. That's eBid's job.
I think the only proper place to discuss items that you think are misplaced is in the forums, NOT IN THE LISTINGS. I also think you must tell them which category is suitable. A quote from a professor when I was getting my MBA: "Do not criticise someone else unless you have a viable solution to the problem". You are causing fellow members a lot of trouble, then getting angry when they take action to stop you.
For what it's worth, I am a buyer as well as a seller. I NEVER look for an item by category, I use the Search facility and check everything that comes up. I do that on ALL sites, not just here.