bipface said:
one kind fulfils a need, the other does not

You can live without either one of them though

Fenrick said:
You can live without either one of them though

if we're talking that literally, the only things you 'need' are water, nutrients, sleep, medicine, protection from environmental hazards, …

if we're talking common sense, it's a matter of personal priority
'I need a vehicle so I travel to my job and home each day'