Oil is not hazmat, you dump some on the ground and it won't kill the neighbors cat;
According to :
The U.S Environmental Protection Agency, National Pollutant Discharge Elimination System (NPDES) :
Used motor oil is a hazardous waste. It contains heavy metals, contaminants and dirt discarded by the engine during use. Fortunately, used motor oil is dirty rather than worn out, so it can be recycled. However,
motor oil is toxic to humans, wildlife and plants.
Costs;
Costs for used motor oil recycling programs vary depending on whether a community has already established similar types of recycling programs. Major costs associated with oil recycling programs include costs for advertising and oil collection. While service stations and collection facilities often allow the public to drop off their oil free of charge, these facilities must pay a recovery service to collect and dispose of their accumulated oil. One such recovery service, US Filter, charges an annual fee of
$179 for unlimited waste oil removal, or a $79 fee for one-time oil removal, from service stations, small garage owners, and other types of collection facilities. Costs for programs also vary, depending on whether oil is collected by curbside pickup or at drop-off facilities. As fees vary, check with a local recovery service for more specific information about oil collection fees.
Here is a link to the E.P.A. website.
EPA - Stormwater Menu of BMPs
Now, what "costs" does a manufacturer NOT pass along to the customer?