Plumbing, not potable water certified. ?

[hillegom]

So I have been reading that not all plumbing fittings and pipe are certified for potable water. For instance, spa flex or flex pipe.
Do people really care? Does it matter?
I find a certification (in the states) of nsf 50/51 for carrying away sewage or drainage. And nsf 60/61 for potable water.
Most fittings and pipe certified for potable water cost a lot more than non potable water use. And some pipe, like spa flex, I have been unable to find certified for 60/61
So for you people that have used non certified potable water fittings/pipe, have you noticed anything unusual/happening in your aquariums?
Do you just go to the hardware store and buy parts and not even ask?

Thanks for your input