price spreads, especially for Diesel are amazing. One town can be 30 cents per gallon higher than the next town. I always try to fill my truck at a volume station. Diesel sitting in an underground tank for a long period worries me.
The company I retired from had 2 30,000 gallon underground fiberglass storage tanks for diesel that they fueled their semi's with and they had electronic monitoring on them. They always had a couple inches of water under the diesel fuel. You could see it on the monitor. I sometimes wonder how much water are in your local filling station's fuel tanks. Most stations don't have a sophisticated monitor like my retired from company did.
The, we have the e-gas scenario where e-gas attracts water... another story.