If my memory serves, I learned about this in astronaut Scott Kelly’s autobiography:

https://www.goodreads.com/book/show/29947651-endurance

Peeing on the bus tire became a sacred tradition, and Scott did it when he launched from that site.

And he’s mumblin’

And he’s screamin’

Cause he can’t name

What they’re singing!

Let him wear shirts,

They don’t wanna.

Even cool bands

Like Nirvana!

Not you. You don’t get to know, sorry.

That’s why it’s called ground water.

Yeah… maybe it’s that sometimes the parents forget to leave chocolate, and they say it’s (somehow) the Easter Bunny’s fault. And this comic is in reference to those excuses. That’s the best idea I’ve got.