A 15 foot piece of 12/2 romex cabling is $41. A 250 foot length is only $108.
$2.73 per foot versus $0.43 per foot. Same brand. Same cable. Same basic packaging. Massive penalty for those who just need a little bit to add a thermostat to their baseboard heat.
P.s. they don’t sell 12/2 by the foot.