Well, a Baby Ruth doesn't seem like that silly of a name to me - it is honouring one of the greatest baseball players, not to mention that it tastes lovely. Plus, I'm just used to seeing it sitting on the shelves of Walgreens. 
This was on a Canadian website about the Oh Henry bar (http://www.hersheycanada.com/ohhenryproductpage.asp):
"Created by the Williamson Candy Company of Chicago, the Oh Henry!® chocolate bar came into Canada through The Lowney Company in 1924 and has been one of Canada's leading candy bars ever since. The bar was named after a boy who used to come into the Williamson Candy Company factory to flirt with the girls making candy. Every time the girls need something done, they would call "Oh Henry!". Hershey Canada acquired the Canadian rights to this bar from Nabisco on July 1st, 1987. It is manufactured by Nestle in the U.S.A."
Anyway, I hope that was insightful. By the way, great silly name for a chocolate bar! 