You will have to pay for it because you don't have the capacity to generate large quantities of energy. The companies that do will always charge for it.

300 miles? That's not much of a vacation. I drive more than that in a day when I'm on vacation. But I wouldn't be able to with an electric car.

There is somewhat of a scarcity of coal, gas, and oil for generating electricity. We don't have the land for windmills, without going communist and confiscating it. They also have a negative return. The same goes for solar. It's a losing deal, if it weren't for government (taxpayer) subsidies.

Yes, you can "make electricity" with a home made generator, but you have to physically turn that generator. That takes a force from somewhere. There's not enough wind or water to do it. You can crank it yourself, but you'll get tired fast. Also, you can't get around the laws of physics.

You seem to be blinded by how much you had to spend on the Tesla. Just wait until you have to replace the battery, or start getting fewer miles on a charge. Or you get stuck on the interstate in a winter storm.