We only hear a minor snippet of all the radio transmissions that go on throughout a race and out of those transmissions we do hear, a lot of them seem to be Hamilton ones, so you are bound to hear moans and groans about car performance etc.Saying that, Hamilton was a moany little bugger this year. 'I have no grip...I have zero grip guys' - 'I have NO downforce' - 'These tyres have no grip' etc etc etc. Fine, if you have a problem, tell your team, but at the end of the day you just have to get on with it.
Out of all the drivers I would say that when grip is low Hamilton is one of the best drivers in F1. That doesn't mean he isn't entitled to ask the team if there is any way performance could be improved... especially when you consider the downforce advantage the Red Bull had at every race.
As for Vettel. The fastest man/car won the championship this year. I like Vettel but Red Bull's car advantage was far greater than their eventual points difference showed. Hamilton and Alonso shouldn't have been anywhere near them.