@134318c2 
I'm confused by these reasons.

1) in what sense is calculus required for understanding statistics? Isn't the core concept probability?

2) probability is massively important in daily life and poorly understood (eg the lottery, "hundred year storms", risk pooling, etc.)
What's the analogue for calculus?

3) you think that simple, engaging concepts for teaching calculus are common? Hoo boy, not my take (and I was an A student in math and calculus.)