I realized that my goal is actually for my kid to never HAVE to buy ammunition. Between loaded stuff and components, I could likely go the rest of my active lifetime without purchasing more, even with a fairly decent training schedule. I'd like to leave him enough that he doesn't have to WORRY about it for the foreseeable future should something make it difficult to purchase replacement.
On another note, I think I've instilled that desire in him because whenever we walk through the sporting good section he asks if we need any 22 ammo. ;-)