I agree with the brand names. But as you say, it's a grey zone. I will keep that in mind. I never had problems with it in the past, because it's just an item that's part of the whole picture. It's not that I highlight just 1 brand item to sell it.
I will remove the watermark from next pictures. I was not aware that my own signature was a problem because I have the copyrights. But no probs. I will choose different pictures next time :)