Don't ever take advice from a register ringer at a parts store or dealer.
You can NOT use fuel hose for ATF/steering. You can't even use it for fuel injection. Fuel hose is for gravity, vacuum, or extremely low pressure fed fuel systems, not to be confused with fuel-injection hose.
ATF/PSF are hydraulic pressure lines. To be safe, you want to make sure it can take the abuse for your application. So, using ATF hose on the low-pressure side of PSF is usually OK. Smokey says to prevent under hood fires, use the correct hose for the application.