When I was traveling more often I would always have 146.52 on. I often worked pilot/hams at night, especially out West. Most of the time they were working cargo flights (Most of these are at night).
Once, when driving thru north Texas I worked a pilot who would just say he wasn't civilian and not commercial, so the inference was he was military. Some of the other flights I worked may well have been military, they just probably didn't want to come out and say so.
I used to have a "sched" with a check run flight when I worked midnights, there was a large dual engine turbo-prop that would over fly my town at exactly 0430 almost every night. After a week or so of noticing this I started flashing my spot light and after a couple days he started to flash his landing lights. This went on for a good month or so and I was tempted to borrow a buddies Airband HT from his flight bag and try him on 123.45 but never did... Eventually I rotated off to days and the next time I worked mids I didn't see him anymore.