I wish I could temporarily smell like whatever I wanted, as long as I had a sample of the smell with me

Granted, but you have no control over the power of the smell and no way to tell how strong it will be beforehand. Sometimes it's the faintest whiff, others it's overpowering. At some point it will kill someone's household pet.

Granted. Every time you want to take a shit you smell like shit. Every time you want to eat you smell like the half digested food in your stomach. Everytime you want to fuck you smell like a romp in the decrepit sex pit at the local fuck shop.

Granted. You temporarily smell like one thing that you want, based on something you have with you.

For the rest of your life, you have no discernible scent whatsoever.

Granted but this power drains the thing your carrying. Any Food items turn into a disgusting rot after a minute or 2

You also lose your own sense of smell.

Oh yes, I'd just pick up an apple and enjoy it double

as a side effect, you easily get nose-blinded and the way you know others smell you is you always sneeze every time someone smells you and as loud that the smelling person can hear it.