Hmmm well if it were me personally, and I was meeting up with someone I had been speaking to off and on for awhile, and they drove a ways to meet up with me, then realized before the meal he had forgotten his wallet, I'd have wondered, but given the benefit of the doubt, offered to treat him this time, but taken note whether he made any effort to treat me another time or not. I would have chatted and talked, and if he took off never to be seen again and just wanted a free meal, he sure went to a lot of trouble for that and I guess I wouldn't sweat it that much, just would chalk it up to a failed dating experience. Sometimes you have to learn about people through experience, the good and the bad, and I guess I'd have been willing to take a shot at it if I felt comfortable around him. If I had bad vibes, didn't feel comfortable, I'd just say I wasn't prepared to pay and part ways.

I'd have been a lot more likely to be suspicious if the missing wallet wasn't brought up until after the meal. But people make mistakes, especially when they are nervous. Just how I personally would have been inclined to consider things. I don't know this man you met however and wasn't there myself so certainly wouldn't presume to say that what you did was the right or wrong thing.