Completely different and you know it. The passport is recognised internationally as a physical representation of your citizenship of a state. Why should I have to pay for that? Next you'll want us to pony up for our PPS number
It's not a representation of your citizenship it's a document giving you the right to travel to other countries and only required if you choose to travel so it's only right that you have to pay for it as you actually don't need one to live in the state or interact with the government.
However you do need a PPS number to live in the state and there's no charge for that as it's a state imposed requirement.