Correct, this is not presently an issue. However, as the OP suggests, there is an intrinsic link between mint rewards and apathetic voters. Therein, we can increase security and revenue by solving this issue, which I could argue are always a boon for the network. However, small measures of security and revenue are not vitally important right now, so I agree that this is not high priority.
I took a stab at fully solving the minting equation and it wasn’t too bad. I came out with the statement that increasing the minting rate from 1.025 to 1.05 while keeping a 35% mint rate siphoned money from the non-minters at an increased rate of 9,250 NBT/year. The siphon rate is maximized at 50% mint rate (not surprising) and it’s somewhat linear near unity mint rates. We should be able to get ~4 kNBT/year/% mint reward as a form of dividends paid by non-minters.
I used mathematica, the equation isn’t super simple so I’d rather not post it. Let me know if anyone wants to see it.