Because it saves them 50 cents or less per vehicle..........
When I bought my 1983 Chevy truck, they tried to stop putting spare tires on them that year. They wanted $230 for a spare tire as an extra. Luckily that bright idea didn't last long.
Bill
Nodwell RN110 out moose hunting. 4-53 Detroit, Clark 5 spd, 40" wide tracks, 10:00x20 tires, 16,000# capacity, 22,000# weight. You know the mud is getting deep when it's coming in the doors.