Ok so here's the thing, High Sulfur Diesel is imported, and I highly doubt that's what you're seeing. I could be wrong, but there's just no use for it anymore since the Fourth Reich *EPA* has gone off the reservation on Diesel emissions. The pump might be old and have old labeling, but more than likely it's off-road diesel.
You might be seeing Low Sulfur Diesel but that's going to be dyed red and for off road use only. Don't quote me on the color, some states use green, but Red dye has been the standard.
ULSD is used in ALL OTR diesel applications now. Only reason they keep Low Sulfur diesel is because of agriculture. Tons and Tons of farms still use diesels that need that extra sulfur for lubrication in the mechanical fuel systems. Otherwise I'm sure the EPA would figure out a way to screw over farmers even more than they do now...