A friend of mine and I were discussing this very question the other day.
I haven't noticed any effect at the BE matches I attend, but hardcore BE shooters tend to maintain their own stockpiles. And we already have a 22 stage. I'll have to ask the match directors whether they're noticing that more people are laying off of the centerfire and 45, and only shooting the 22.
But HP matches could be affected, not only due to ammo and components costs, but also the run-up in AR prices. HP can be expensive even in the best of times.