My thoughts.
1. What you did was obviously LEGAL. Otherwise, he would have ticketed you. That's not the issue, as you know.
2. As for it being proper etiquette (your question), I would say that since there was a squirrel and crow season, you had both a legal and ethical right to be there, *IF* you were hunting a specific species. You were not, so in my opinion, it's bad etiquette to shoot/plink in a public WMA/GMA/Forest when there are any actual seasons going on (be they deer, squirrel, or multiple), because of the chance that you'll molest their hunt. Furthermore, IMO, it's bad etiquette to EVER simply just plink with a gun, unless you are trying to actually take some kind of game, or cull a nuisance species. But NOT plink at objects like trees, rocks, etc. That's what gun ranges are for. We don't need to fill up our public lands with lead, empty shell casings, and scarred trees for people to plink. They are there for hunting, fishing, or otherwise enjoying the land without messing it up. Simple solution, however....next time, actually look for, stalk, and shoot some squirrels, a nuisance species, or whatever else is in season - it's fun, challenging, and you'll have a nice dinner or 2 when you get home. Then, if the game warden confronts you, you'll have no compunction about telling him (in a nice way) to stick it where the sun don't shine. But if you're just plinkin', then I agree with him. And there's the issue, as mentioned, of bowhunters being very hard to spot, so it's hard to know whether you're right up on them. They'd love for you to spook game up to them, but not get within 100-200 yards. Well, I have to backtrack. Actually, I think it would be bad etiquette to be hunting a nuisance species like coyote during a season, particularly deer season (of any type), since you can hunt nuisance species all year long, but they (we) can only hunt deer for a relatively short period of time. If it's squirrels or rabbits or crows during deer season, although *I* wouldn't do it, I say have at it if you like. The proper remedy for us, as deer hunters, if people molesting our hunts actually becomes a big problem, is to campaign the wildlife dept. to pass a reg that temporarily suspends the 8-month squirrel season during the deer seasons, if we don't like it. In fact, I think that would be a good idea, to suspend temporarily squirrel and rabbits during deer, particularly archery deer, or perhaps even better as a compromise, something like weekdays during deer season, squirrel & rabbit fine; but on weekends during any deer season, the small game hunting is temp. suspended.