Barca always needed to get around 5-10 points in a season more than Madrid to win LaLiga. It's not news, it'll never change. They can't seperate sports from politics.
That said, Sociedad threw the game yesterday and not the ref. They had chances for 5 clear goals, they didn't score once. Absolutely pathetic finishing and that's a problem for most spanish sides for years now.
We profited from poor finishing 2 seasons ago as well, when we won many games 1:0 or 2:1 and the opponents didn't score the most clear chances. Many LaLiga teams focus too much on playing with the ball, on tactics in my mind and forget how to score goals, which is eventually the most important part.