^actually. I don't know ahead of time when I'm going to need a trip to the ER.

If I had a date with him and he needed to go to the ER and had already run out of people to call I wouldn't ask him to take a cab and call me when he was all done at the hospital.
The guy didn't have other plans since we were supposed to go out.
I turned out that I needed to get an injection at the ER and since I hadn't found anyone else to take me he could have taken me and then we could have tried to make the best of the evening.

It seems like you also feel like you would need to know someone better before you would be willing to be a friend to them that way.

Your different from me.
That's is fine.
You wouldn't do something like that and I would.
If the guy was really interested in me it would have been a way to show it.
It doesn't feel like it's "imposing" when you WANT to be there because you really like the person and are not pretending to be very interested in order to flatter them hoping for seduction.