Pass the mustard

I do not get the mustard fascination here. Four of the women here put mustard on everything. We had steak tonight, a real treat, and what do they do...they smother their steak with mustard. What?!? I don't get it. They put it on their broccoli, their meat, their shrimp, I even witnessed mustard applied to celery sticks. I watched one pile a lump of mustard on her plate after dinner and licked it up like an after dinner mint. They say they are hungry and it helps to fill their bellies. ok, whatever.