I buy the Premium Travelers oil from Tractor Supply so I called them when it was time to dispose of it. I called two different stores and was told they didn't collect it at both stores. I needed to go to the second store I called for something else so I asked to speak to a manager. I explained I was disposing of used oil I had bought from them and the story changed. I didn't even have to pour it in their tank when I got there. The guy said I could just set the buckets by the tank and he would empty them later.
Prior to that I have set the buckets beside the waste oil collection at our local waste collection center.