It fits with the misguided belief that
if they need it and especially desperately need it,
they will want it and buy it.
So they carry that thought into the conversation
with the poor person who gets hammered by the
over zealous saviour to the man's woes.
Saviour walks out battered and confused.
Because he doesn't know the difference between a need and a want.
A neghbor who has unsightly overgrown grass on his section
needs to mow his lawn and he knows it, but doesn't want to,
therefore he doesn't take action.
Want is where people take action.
The people in the street have neat and tidy lawns because
they want them that way.
The one with the overgrown lawn doesn't want it neat and tidy.
He wants to be drinking with his buddies
He wants to go fishing with his buddies
He wants to stay at home and watch porn
Past behavior is a great indicator as to whether people want something.