Oh. Right. You just introduced the concept of non-anonymous (to the orphanage) matching funds. I didn't think of that.
More money for the orphanage means more orphans can be taken in. That's good, right? But since the extra funds are not anonymous (to the orphanage), then it can come with influence on policies.
Policies like: All orphans are now accepted up to a certain age regardless of circumstance, and all orphans now get kicked out at age 12 regardless of ongoing need.
The stated reason is that the orphanage only has so many resources, and little kids need a lot more care than 12-year-olds do. So a line must be drawn somewhere, and that line is at age 12.
It's a popular policy: After all, when given binary choice, everyone would rather see a 3-year-old be taken good care of than a 12-year-old. Think of the little children!
For the orphan crushing facility that helped to impart this policy with their very generous policy-adjustment matching funds, that's a solid win: The orphanage now acts as a livestock kennel where orphans grow in size. There's still fewer of them coming out the far end, but they're bigger than they were before and are now much easier to process in bulk.
People know about the orphan crushing facility. They know they can't do anything about it; it just looms over there like any other dark fact of life. But the streets aren't full of roaming herds of abandoned kids anymore at all, so folks logically conclude that the 12-and-out policy must be working.
Out of sight, out of mind.