The wild jiggaboos aren't even the biggest problem (presumably you're armed anyway in case something happens). Trains and buses are a useless alternative to cars if you're out in the sticks, where there's no tracks or stops/stations for miles, and even if you live somewhere which DOES have some sort of coverage, you're at the mercy of their time tables. You're not taking the bus to your local store if the nearest bus stop is even further away than the store, or if there's no stop near the store in question.
The kind of people who tend to argue that we should all stop driving cars and just ride the bus or the subway instead tend to be very urban, and have never seriously thought about the insane logistics required to make it actually adequate for rural people. This gets extra funny when you consider that the viewpoint tends to be motivated by climate envangelism.