I do the same thing a little bit since vending machine quarters tend to have slightly more variability than other sources. The very best quarters are from rolls you obtain at laudromats or similar operations. Just so you know the coins you receive come from magazines that can't be refilled until the machine is serviced. If you empty it you cause the light that says "correct change only" to come on.
The rolls you get from banks are very nearly as good and it's possible if you find the right bank that they'll be even better. It certainly is a lot easier to pick these up at banks than to empty a machine and you'll get fewer "looks".
I have no love for the vending industry since they kill six or eight people a year with top heavy machines that the government won't require them to bolt down. I've been ripped off more times than I can count. I think of these machines as traps to catch people but no one seems to care since a majority of those killed are thieves. One of these days they'll get sued and then they'll bolt the machines to the floor.
Time don't fly, it bounds and leaps.