There are none of those stations anywhere near me. Around here we have Mobil, Valero/Valley, Sunoco and Citgo to a lesser extent for the main chains. By far the most common is Stewarts, a convenience store usually with few pumps, but from what I've experienced they sell some really **** gas, every time I fill up there, with anything, it runs like crap afterward. There's a Lukoil here and there, but not many of those.
I typically fill up at the local Valero(now Valley, but it's exactly the same), since it's near my house, has pay-at-pump, and is usually one of the cheaper stations.
But then again, what exactly is this "top tier"? What exactly are the standards compared to "regular" stations? Their website is extremely vague and sounds like the back of any snake oil bottle....your car will run better, have less deposits, if used regularly it might become able to fly....yada yada yada. It does not list any actual evidence or comparison between. Wouldn't be at all surprised if a few oil exec's got together and started selling admission to their "top tier" club to the highest bidder.
Reminds me of that book "The Jungle"....how 1 in 3 steaks was randomly marked as "special" and cost an extra 25 cents a pound.