Everybody loves Mickey Mouse, so, I don’t know why E.T. wouldn’t, also.
Here is something that folks should keep in mind when trying to determine if something is the result of extraterrestrial intelligence.
Not everyone likes Mickey….don’t forget “Pete”, or in Steamboat Willie he was “Peg Leg Pete”
E.T. could have put it there just to piss “Pete” off….you know it’s probably more likely…