Well to be fair ---- Cafe Wha? is a bar, so Dave was just adapting himself to the surroundings.
Sammy only drank onstage to sell the sheep more of his tequila and trying hard to outdo Jimmy Buffett.
Alcoholism is basically rooted in some kind of emotional pain ---- and in 2004, Eddie was still depressed over being divorced from Valerie, and working with a greedy shitbag like Hagar certainly didnt make himself feel better inside.
I honestly believe it when Eddie says Wolfie and Janie are keeping him on the straight and narrow ---- those are the two people he loves most in this world and he's got a lot to lose if he breaks his promise to them.