I the 80's/90's when I used to read Metal Forces I was the same way. But to be honest mediocrity never atracted me. In music or in movies ...That is fucked up. I would say that at RC, even a 7/10 score is still worth checking out. 6/10 being 'above average' so most people would probably be indifferent. But a 7/10 could easily be someone else's 10/10 if you know what I mean.
With that said, I used to do that a few years ago myself. I would visit Metal Rules and Metal Observer and only look at reviews with 5/5 or 10/10 ratings, and just ignore the rest. Shame on me I guess.
Being average is quite frankly boring. I would rather give something that is a 3/10 a shot just for shock value than something that is 7/10. Stupid? ... Maybe
Unfortunatelly, those mediocre bands never make it just because there are a lot of people like that out there like us, that will never give them a chance.