Where do specific gas stations import their oil from?

I have heard rumors on this topic, such as “BP does not import Middle Eastern oil” but I don’t know of a good place to verify this.

Does anyone have any data or expertise on this subject?

Also, I’d love to hear your opinion on purchasing patterns for gas:
– Do you attempt to only buy gas from certain places? Why?
– Is it important to you that gas be imported from non-Middle Eastern locations?

Just wanted to see what the collective thought about this so I can make better choices based on my own personal beliefs on the topic.