faa waiver

I have seen a few places where folks bring up the altitude waiver when talking about MPR launches at a club and I was hoping the collective mind could help clarify something for me. Why does the waiver matter for LPR and MPR? According to NAR's own website, which references FAA 14 CFR 101.22...

There is a particular Military Base (Bradshaw AAF) that I would like to approach to see about doing either an annual or semi-annual HPR Launch Day(s). The airspace is restricted (of course). I think (that's probably dangerous) that the FAA is not involved since it is an MOA. I need some guidance...