A stick-and-ball game derived from the old Irish form of hurling, played on the Isle of Man. A game my father taught and played with my brother and and me as young boys. The so-named candy bar came late in the game.
It's grainier in the United States; that's certain--because they deliberately make it that way. Depending on the candy bar, the chocolate varies (so KitKat chocolate differs from that of a Hershey almond bar, for example). Also, most chocolate makers take into account the "national" tastes of whatever country's consumers will be eating the chocolate:
"A KitKat bar is the same the world over, right? Wrong. Leave aside the Japanese variant, where strawberry, banana or other fillings change seasonally; even the more commonly found chocolate-covered wafer bars can look and taste different depending on where you buy them. A Russian KitKat is slightly smaller than a Bulgarian one, for example, and the chocolate isn't as sweet as in a German one. It's the job of a Nestlé confectionary factory in York, England, to juggle these small nuances in taste by adding or subtracting key ingredients like sugar or cocoa during the production process, depending on where the finished bars are slated to go on sale." -- "Taste Test: Same, But Different,"TIME
I don't care which KitKats are better because I'll eat them no matter which company made them. I love those things.
That said, I have noticed a difference in flavor between Hershey's and Rowntree, but I think it's because the chocolate is different. That is to say, I think when Hershey licensed the wafers that they agreed to make them the same way... Well, who cares. Anyway they do taste different. But they're both good!
I don't know (or care) which KitKats are better because I try desperately to stay clear of both. However, I did used to make the little buggers in the plant (which I'm sure I mentioned before)--so uselessness, that's why I'm planting this perfectly use(less)ful knowledge here. :-)