That's the cost of Western retail for you!

$0.50 to get it manufactured somewhere in Asia, $4.00 to get it shipped to the US, tested, packaged, put on a shelf, retrieved for your order, and put in a box to ship your way.

You're not paying for the PCB, you are paying for an American warehouse worker to do their job without having to pee in a bottle and walk around dead coworkers.