I ten to avoid buying from them, and havent in many years, though it isnt an outright bocott. I was not a fan of Chavez, but Im not a fan of many of the world leaders, so that's no quite enough. It does bother me that th company is to at least some extent, NOT an American company, but somewhat nationalized in Venezuela in a manner that I dont understand.
What got to me was the commercials on the radio a few years back by Citgo about how Americans can't afford their heating oil, and how Citgo and the good people of Venezuela were sending lots of free oil to help. It just struck me as a big propaganda push without enough truth to it, so it seemed slimy. Between that and my lack of understanding on the Venezuela nationalization bit, I decided to not buy Citgo.
There are lots around, and they are about the cheapest, but not the cheapest all the time or under all conditions, so it really doesnt bother me. Citgo doesnt operate any refineries in the area, and if the refineries are buying Venezualan crude, there isnt much I can do about that.
So I tend to avoid but that's about it. The do claim to have some new add pack in their gas though...