First, Miami is the better team or collection of individual talent, however you want to word it. They were better even before Bosh came back but with Bosh in the mix, we cannot match their overall collective talent. The Celtics were tough and gritty and gave Miami more than anyone expected but we are not as good as Miami.
As for the conspiracy/refs carrying out the mission of the NBA theory, there is no doubt that the shine from the stars does get into the refs eyes and imapacts calls. The bigger the star, the bigger the shine, the more calls go your way. Reputation is a factor too. If you have a reputation as a good defender, you get more charge calls. If you have a reputation as a stiff (cough cough Steisma) you get called anytime you are anywhere near contact. I don't like this especially when it goes against the Cs but it is there, no doubt.
Conceding that though is still a long way though from accepting the wizard behind the curtian predeciding how everything is going to go theory. Come on, really. Let's be good sports and just accept we lost without blaming the refs/NBA.