Unless there is more to this I can see his point. He is saying that the woman could have waited in the bar for an hour on her own. I don't see the problem with that, plenty of women do that, away on business or just killing time, perfectly safely.
It would be different if she was standing on a deserted railway platform but you say she wasn't. Also, if you had not been there, if you had not gone on that particular night out, she would have had to wait on her own so whilst it was kind of you to offer, it does not sound necessary to the safety and wellbeing of your friend.
The other thing is that you made this arrangement with your friend before asking if it was ok with him to come out an hour later than arranged to pick you up. That is bad manners. It would have been better to phone him and say don't worry about picking me up, I'm going to get a taxi as I'll be an hour later than planned.
Then, if he wanted to, he could have offered to collect you anyway and, if not, he could have got off to bed, or watched tv, or whatever it was that he wanted to do that evening.
Finally, if he is telling you that he feels you put your friends before him, listen to him. Talk about it and find out how you could both work together to make this easier for everyone.