Joseph, most Israeli Yeshiva Bochurim do not have driver licenses, most yeshivos do not let their bochurim get one. So they could not borrow their fathers’ cars even if they had one.
Also, in the chareidi world, a car is not considered a necessity, and is often beyond a typical kollel family’s budget. Besides the cost of the car, insurance is very expensive, gas is about twice what it costs in the US, and just getting a license is a fortune- you have to take something like 28 mandatory lessons, besides the test and fees, so it can cost thousands of shekels.
So going by bus is the normal thing to do in Israel, even for a date.
I always did wonder though how tznius it is when everyone on the bus sees the girl dressed fancy on a weekday- and knows exactly where she is going, especially if it is during sefira when she can’t be going to a chasuna.