I may be a vanishing minority, but I have always been a loyal customer of a LOCAL business that will go out of its way to treat me right. Here is an recent example. I went to my local dealer intending to get one new tire to replace one because the tread was obviously worn down.
The dealer took a flashlight, crawled under my fifth wheel and inspected all tires on their inside faces. One tire which I had thought to be ok had knots or bulges on the inside. (This would be the sixth season for that tire; I was trying to get one more season out if it.)
Most dealers wouldn't do that. The one that does is the one who gets my repeat business.
Maybe I could save ten or fifteen dollars by buying online. But one blowout could cost me a thousand dollars in structural damage.
One more thing that puts me in the minority. I have had two blowouts since getting my fifth-wheel. Both blowout involved LT tires. The tire with the knots mentioned above was an LT tire. Going against the grain, I have been replacing LT load range E tires with (GOOD quality) ST tires with load range F.