Parsnips vs. Turnips

It just happened again. TPP was buying parsnips to make some sausage, lentil, and parsnip soup. The check-out clerk had no idea what the parsnip were and so could not enter the correct reference number. The helpful know-it-all bagger said to the clerk, "You don't know what parsnips are?" And then she adds to me, "They're just like turnips." Amazing. Why do people think this?  Other than having the same basic color, they are nothing at all alike, so obviously the person speaking has never eaten them. Parsnips are much tastier, much sweeter, and a much under appreciated vegetable. Turnips are not a favorite and fall somewhere below kohlrabi on TPP's list of vegetable likes. But why do people think parsnips are like turnips? And nobody ever says, "Yum, turnips."  Is it the -nip thing? A sounds the same, tastes the same kind of association?  Here's TPP's advice on parsnips. Never ever boil and mash them. This is a crime against a nice root vegetable. Peel and slice the parsnips into 1/4 inch thick pieces, cross-wise or length-wise. Par boil for about 8 min. until just tender. Blot dry, and sauté in butter on a griddle until lightly browned and a bit caramelized. Parsnips are quite sweet with a quite unique taste, which is nothing whatever like a turnip. Here's another rule: don't write a blog and try to cook sausage at the same time, you might burn them.