These Amazon FBA numbers are surely wrong?

How do companies selling stuff on Amazon FBA for like $4 make money, considering the fulfillment fees are like over $3?

I must be looking at the wrong numbers, surely?

I’m using the Costs Calculator in seller central (I’m currently going through seller university as if it were a real university… I’m not selling yet) and these numbers are very demoralising.

For example, if I wanna sell private label Jelly beans at $4 a pop… The FBA fees basically wipe out any possibility of listing at that price.

My question is… How are people doing it?

Is it just a matter of miniscule margins?