I think as PhD students one should put away that element of pride. Agreed, a non-PhDer might not know wha the heck you're on about but an advice is an advice.
From personal experience, i have learnt bits an pieces from people not related to my field in any way and are, quite frankly, scared of it. This should no stop anyone from receiving advice from someone who isn't doing a PhD.
In any case, an advice is an advice, it is your decision if you choose to accept it.