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flagpole concrete

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A previous post inquired about flagpole foundations vis-a-vis UBC 1921.2.4.
It requires 3000 psi concrete in structures resisting earthquake forces.

I feel 2500 psi is appropriate for flagpoles (and by extension larger
monopoles) a few reasons:
1) note the code offers 2500 psi as an exception for footings of bldgs <3
stories.  So the precedent is there, at least.
2) wind generally _controls_, not eq.
3) the failure mode is generally not catastrophic (the footing is contained by
soil, occupancy is low, etc.)  By the time the footing gets big enough to
account for soil allowables, it's pretty big.
4) In cases where the pole extends down into the footing, the concrete is
essentially "strong backfill," and is structurally redundant.  (Contractors
seem to like this arrangement, and I do too.)