People wed to a brand will buy them...
I have a S&W M&P 15 Sport and though it's a budget AR it's a long way from junk. It shoots so well I have my 4.5-14 scope on it for the next trip to the range. For those who missed it in the other thread...
10 shots 100 yds with handloads. (hadn't finished zeroing the scope yet)
I've owned a Norc and it shot pretty well in spite of it's inferior finish. The Ruger may very well be junk but cheaping out here and there doesn't necessarily make it so. My M&P has a few things missing and it has a 1 in 9 barrel but it's run like a champ so far and that six shot cluster is pretty impressive (and it's not the only one like that).