See, I disagree with that both claims, but the latter has already been debunked previously). I recently had the displeasure of trying "the best fried chicken in Batesville, MS" (Mr. Jiffy), both locations of which are in gas stations (NTTAWWT), for the second time, and once again I was quite underwhelmed.
There are a lot of factors that go into fried chicken, not the least of which is turnover of product so the chicken is fresh out of the fryer (although you would think that wouldn't be an issue with "the best" chicken, but I digress). I am also not saying there is anything wrong with chicken that has been sitting around, but that's a different discussion.
Anywhoo - everything else being equal (which of course it isn't) - the thing that dooms gas station chicken is that their displays are enclosed, which effectively steams the chicken (moreso if there are other wet sides in the same case), making it soggy. Grocery store chicken is usually exposed to circulating air in a buffet situation, so if chicken is being replenished, it will have a longer window of staying crispy, making it more likely you will get a superior product.
QED
And Happy New Year!