I agree that this was handled wrong. But its also worth considering how his girlfriend and family actually felt after the event, they were probably not thinking as logically as you or I.The family and police would have surely known soon after the crash if he'd been drunk etc, but they made celebs/singers put on an event to celebrate his life (which is fine as a family) but I'm sure a lot of big names feel stupid for agreeing to it without knowing the full details. Considering it was he who was drunk I'd be sad still for the loss of his life, but would have felt sick to be associated with something like that when it's one of the worst/stupid things people can ever do imo.
But my main issue was with the fact you have people insulting the dead. Quite frankly is shameful and extremely distasteful.