Well, mostly it is exactly so, as I am an academic, my wage is paid be the Italian state, coming from general taxation, and I provide free answers and consultancy to privates.
I also do some research contracts with big companies, and in this case they pay my University (but not me directly).
When I was young, before working for 5 years as a professional scuba instructor in commercial resorts, I was for 6 years a CMAS instructor, teaching for free as a volunteer in my club.
I am still a volunteer in "Civil Protection"...
And I am also an off-service firefighter, which means that they can recall me at any moment if they need my help. It is very nice not to worry about being paid when doing your job!
But of course we are going off topic.
The point is not me giving instruction, training or consultancy for free, which is just fine, the point is if issuing a duplicate card is worth 45 USD...
PADI is a money-making organization, and they are excellent at this. Usually they provide quite decent return for the money you give them: if not, the market rules had already destroyed them, as they have excellent competitors, but still they keep the edge. Which means that they are not that bad, both in training and in other stuff.
And this is proven by the fact, albeit both I and my wife are CMAS instructors, and both our sons had got also CMAS certifications, we sent them also to PADI courses. So now they are aware of the "other" way of diving, which in the end is the most widespread one. And they have no problem adhering to the procedures and safety rules employed in most places all around the world.
Back to the card: as PADI will update the card of my son to an adult AOW without need of further training (which of course he does not need at all), I will be happy to pay those 45 bucks.
If instead they had sent us just a copy of the old card with Jr AOW certification, I had saved those bucks easily, as in most places a printed copy of the card is all what they need (for their archives), and PADI shops can easily check the certification online also without exhibiting the plastic card.