There is more demand for pinball games than there are machines to fill it. This has been the story for the last 23 years or so (think it bottomed in '97-98?) Prices been going up ever since.
Problem is, right now_ the demand for games is far exceeding supply, mostly thanks to covid hosing up the supply chain. Every owners' thread here is filled with future owners waiting on backordered machines. How many thousands of games is Stern behind?
Stern cannot allow themselves to become backordered til mid 2022 on mid 2021 prices, especially when labor and component costs are rising a fair bit more than they have in the past.
Add in additional demand from everyone helped with stimulus (left) or lower taxes (right) and these prices increases are pretty much what one would expect. Sucks, but like others have said, everything's getting higher. I can sell my old games for newer ones if needed.