I think of this differently. People need food, they buy a hot juicy steak. People need shelter, they buy a home.
Needs are categories. We don't sell or buy categories, they're one level of abstraction removed. The real problem is when the client/seller thinks they're selling a need, what's happening in their mind isn't seen in sales. People who think they're selling "needs" have bought into they're own
PR. The only accurate thing you can predict is they're on the verge of making an unpleasant discovery.
Case in point. A builder is offering "shelter" and going broke. People are visiting his units and going elsewhere. The builder then built bigger, more luxurious houses, and kept the price the same by having the upper story unfinished and sealed off.
He's offering "more" for the money. The unfinished space can be completed when the money comes, pay raises are realized, etc. And this way, there's no need to go through the trouble and effort of house hunting and moving and refinancing and relandscaping.
There are a number of companies who thought they "owned" a need, only to find a competitor came up with an innovative alternative which showed it was only another product or service in a need-category. The market may shift tomorrow and people may express that particular need by buying something different.