EDC Grand Master
I really don't know if I ever saw the film???
I did, however, read the book...... A few times.....
All in all, I think a horse (or any living pack animal) would be terrible post SHTF. Look what happens to horses in The Walking Dead. And war novels. hehe....
I think a good bicycle would be a nice way to 'travel'.... No worries about engine issues or noise. Quick & small enough to go around cars, even be carried if necessary over rough terrain.
Easy to fix, maintain, and probably easy to find spare parts, even a whole new bike in about any person's abandoned garage.
Worse comes to worst, you ride on the rims with a popped chain 'scooter style' until you find a better bicycle.
Plus, you could always jerry rig a kiddo tow behind cart as a sort of trailing Bug Out Cart, which could be detached from the bike and put on new one, or just pulled behind you walking to get weight off your back.