To add to @garbagebagel's point I am not sure that a homeless person with a car is very common in Eurasia.
But come to think of it, this depends on how much people are willing to move around and at what point are they considered homeless, e.g. if they can't afford to sleep anywhere except for the car but have a room in a next town etc.
Also, I am now not sure what is the statistics of ownership of things like cars in a group of homeless people in different places. Could be wrong about the idea that most homeless own close to nothing but don't know if such a statistic exists.
Oh definitely, it's not a great option regardless so if you have the ability to pay, the gym is definitely the better option.