Lots of folks are saying that this is an indicator that the banks are withdrawing coinage from circulation in preparation of 'going cashless'.
My suspicion is that this might be another hint that a 'reset' is getting closer. Consider that if we do have a reset, new dollars might, for example, replace old ones at a rate of 1:100 (or 1:1000?), meaning that you would get $1.00 new dollar for each $100 in old dollars. The coinage, by comparison, would still be valued at face value, so a nickel will still be $0.05 in new dollars (equal to $5.00 in old dollars in this example). Stated another way, if old dollars are devalued at a rate of 1:100, coins will be 'worth' 100X what they were before the devaluation. This is a good reason to hoard coinage independent of the value of the metal in the coin (NOTE: A 'Nickel' is 75% copper, 25% nickel).
It's hard to say exactly what the gov't would do, but this is a worthwhile consideration.