Yeah you said he was right by his house, otherwise if it was someone you didn't know then I'd of had you call the police. I'd still have taken the keys though while he was snoozing just to keep him from driving off, then called the police. Wouldn't stand next to the car though and announce hey I got your keys if he wakes up. Nothing worse than an angry drunk. Just stand back and enjoy the perplexed search as he wakes and attempts to figure out where his keys are as the police are on their way. Then when they arrive I would give the keys to them and skedaddle. Gee is that how you spell that lol.

A nights entertainment though it is terribly sad.