it's really stupid that he's getting angry over this since there is public transportation to go there. He's using you.
Also how comes no one has a driving license and can't borrow their parents car? Jeez, I thought getting a license was the top priority for any 18 years old.
Just go with them on public transportation and not your car though because that would be stupid and look egoistical.
If you want to go there by car, carry them all and suck it up about your "friend".
The not being comfortable thing can be solved if they aren't a-holes and understand that you need to focus. Just stop and act psycho if they're noisy.
Make them pay for the added gas expense due to their weight and for the favor (since they can't return it because they're deadbeats), e.g. by paying for your entrance or a drink at whatever place you're going to.
If they can't be mature about it, then Vdub is probably right.