Just Because

It was there

Because** Poly** said so!

Red Dura-Pex as well?

were you inspecting the home of dr. suess

Now it does look like something from a Dr Suess book.

It looks to me like someones attempt to set up a tempering system for a whirlpool fill. Red pex is common here on newer installations, used to indicate hot side, blue is used for cold.

This is the creation of a Licensed Plumber.

It looks like the hot and cold routed to a hand sprayer. Since the poly was already there, he stuck with the same type of materials.