A corny joke often makes you groan because it is old, stale or stupid, but it may make you laugh. For example: when the comedian says, "Take my wife . . . please!. You probably heard it before and it's silly but you chuckle anyway. For more corny one-liners see my hub: "Tribute to Henny Youngman - King of the One-Liners/"
An Indian (American) was playing fetch with his dog on the edge of a cliff. Of course, at one point he accidentally threw the stick over the edge and the poor dog went leaping after it. The Indian paused and then reluctantly went to the edge to look down. To his dismay, there lay poor fluffy, dead. He shook his head and said, "Dog-gone."
Ha! I sent my students to a good BBC site to review novels for the state exam, and I told them that the videos are good but a little bit "corny." They looked at me and literarlly said, "Huh?" "Cheesy?" I said. "Ohhhh...." Maybe corny jokes are over their heads. LOL.