Hitler did not get away with anything - he didn't face justice in accordance with common sensibilities but he ultimately paid the ultimate price for his deeds.
There's often a weird dichotomy with regard to the suicide of common hate figures, in that folk who clamour for the death penalty will be furious if such a figure commits suicide on their own terms, as if they've taken an "easy way out". The end result is the same, after all.
An interesting case in the UK is that of lan Brady, a vile child killer who was convicted in 1965, during a moratorium on the death penalty. Public opinion at the time was that Brady should have hanged, and this continued long after the final abolishment of the death penalty in the UK, as if an exception should have been made for this particularly despicable individual. Then a few years ago he resurfaced, having languished in a hospital for the criminally insane, bringing a court case forward arguing for his right to be transferred to a regular prison so he could refuse food and die - whilst he was considered insane, he could be legally force-fed through a tube. The same public who had demanded his hanging for decades and were furious about the supposedly cushy life he lived behind maximum security prison bars were now in uproar about how he should actually be forced to live, that he didn't deserve to die on his own terms and should continue to suffer the harshest treatment possible. I personally couldn't have cared less about the fate of lan Brady, he's a thoroughly despicable individual who deserves no sympathy, but it's interesting how the same people who say "hanging is too good for them" when bad people aren't executed will also say "he cheated justice like a coward" when they take their own lives.