No, that's because pizza boxes are contaminated with fat. That messes up the paper recycling process. Water is fine.

Man, if that's the problem then I can only assume any fast food box is not recyclable too?

	▲	teiferer 2 hours ago \| parent [-]
		The point of paper fast food boxes is not to recycle them but to have no trash in the end as they just burn or rot, all in a sustainable way. In contrast to plastic.