I play cdda. The map generation can be wonky but there can issue of roads overrun by either zombies or abandoned cars. Cars become super useless when you have 1 mile stretch of road you can use untill you clear out the roads.
Also detail that if you run over zombies the bones(or even random crap in pockets) can pierce the tires or wear down the tires.
Horses can be useful but I never use them in game because bikes are more accessible. You could use horses to attract zombies (off roads or into ditches).
The most useful thing horse would be the manure since cars and bikes can’t produce that.
Sorry it didn’t answer your question but wanted to share that
Side note. People can make biodiseal from fast food oil for cheap and animal fat, I highly doubt farmers or truck drivers could get the quantities need
I thinking stenographers. Back in the day people had to learn short hand to get jobs, but shorthand has been forgotten