Auto transport carriers want to move vehicles that pay cash on delivery. This is because carriers have a lot of expenses while they are on the road, and having cash on hand to pay for fuel, food, lodging, and maintenance is of monumental importance for keeping their business going.
"Cash on delivery," though, is usually meant to be read as "certified funds," or, funds that cannot be refused. So, payment via cash, cashier's check, or money order are typically included with "cash on delivery." Note that credit cards are not acceptable forms of payment for most carriers.