That's fair. I did want to do something like that but I was kind of worried that giving too much information would make the game more about the math problem of comparing two things and less about the trivia/guessing dimension of trying to guess sizes yourself.
It's also turned out to be pretty of difficult to figure out a system that can display both a hamburger and a mountain to scale at once in any reasonable way, and i didn't really have the time (and hud space) to figure that out.