It all depends if I was busy or not,
If I was bored as fuck and wanted to make money, as he was clearly willing to pay. I would have done it, because money for driving is pretty easy.
I also would have made him buy me a case of beer, then invited him over to my place or went to whatever party he was going to and drank all his beer and my beer.
Then I woulda beat him at Injustice and MK.
You must live in a small town then? or the country? or it was late and most of the beer stores were closed? Cause thats a hellova long way to drive to get beer.
Also, maybe that dude was having a really really bad day, and couldn't really talk about it with you, but just needed a few brews to relax, maybe he just needed a friend.
I wouldn't feel to bad about it man. If it does bug you and you wanna reconnect with the dude, call him up some time and go for beers.