The guy at Auto Zone said yesterday that you have to use special hose for coolant lines due to the effect of antifreeze, though I have been using fuel line rubber hose in a couple lines.  Will this fail in time, and is there any evidence of that?

Fuel hose is fine. Pretty much any hose that carries fuel or oil will handle antifreeze no problem.

I think the AZ guy is mistaken. His implication is that antifreeze is corrosive to rubber, and that is not the case. The top and bottom radiator hoses in all cars are rubber hoses that suffer no ill effect from antifreeze. Use the fuel hose with no concerns.

 

Rubber hoses cannot be used with brake fluid. Maybe that is what the AZ guy was thinking.