Ahead, Winterhold loomed through the gloom. Dres had no intention of visiting the town today; he only needed to hire a carriage that normally waited for its next fare near the gate. Several hours - even a day - spent traveling back to Whiterun would be miserable enough, but they were well worth not having to deal with the Stormcloaks.
Much to the Dunmer's delight, the carriage was there, its driver nodding off in boredom. Dres prodded him awake and threw his loot into the cart; it clanged loudly. The Dunmer reached for his purse, counting out the twenty septims that would get him back to the more hospitable Whiterun. As he took a seat in the back of the cart, the driver turned around with a sheepish grin.
"Eh." the man said. "Ah canna dee it. She won't go."
"Whatever you mean?" Dres inquired, his patience already wearing thin.
"Ah canna dee it. That's way too much load."
"Are you joking? I could transport it all on a horse myself! If I had one, anyway... And yours - yours has a CART!"
"No matteh. Ah canna dee it. She won't go. An', no refunds."
So yeah. I know fast-travel on your own is impossible while overloaded, but you should be able to take a cart. I'm tired of committing horse theft every time...