Sometimes in older games, they would do some sort of secret area just for shits and giggles in case a player would ever take the bold move to actually explore a bit further or maybe take a different direction.
Instead of Linear Hallways 12 like a lot of RPGs we have now. Not to say Gen I wasn't linear, because ultimately it was, but the truck was a neat thing to see if you happened to surf over there. Really don't think it meant anything.
