It's self-perpetuating
For years there's been the suggestion that little teams can't get a break at Old Trafford. As you say, people will overlook the things that go against them but when a blatant penalty isn't given in the 90th minute of a match that "could decide the title", it adds fuel to the fire.
(Darth Foxtrot A one-man army dedicated to making fetch happen, Wed 11 Apr 2012, 10:06, 1 reply, 12 years ago)

whilst conveniently overlooking the blatant "no foul" that was given as a pen to the "little team"
a month before in a game that has exactly as much bearing on the title?

Remarkably selective memories that ABUs have, isn't it?
( the mighty badger Aphrodite, on a bar stool, by your side, Wed 11 Apr 2012, 10:12, Reply)

I know, you're right
I've personally always felt that the notion that "it evens itself out over the season" is bollocks, but that's based on all we have to go on; personal opinion. The way we got shafted in last year's playoffs can't possibly be rectified, and I'm all for a fourth referee who can advise the ref when he's got something horribly wrong.
(Darth Foxtrot A one-man army dedicated to making fetch happen, Wed 11 Apr 2012, 10:28, Reply)