Instead of conjecture, perhaps we can consult sources that quote period records, such as Sons of A Trackless Forest by Mark Baker, and The Hunters of Kentucky by Ted Belue.
There were many types of hunters, subsistence, market, hide, contract, and longhunters. The term longhunter (iirc) came from the venacular of the time, where expeditions were formed to go on a "long hunt".
In SOTF, it's documented that George Morgan employed hunters for meat to supply his trading post, as well as hides. He sold both rifles and "fusils - neat". The fusils being much cheaper in price,... about 1/4 the cost of a rifle.
Morgan isn't kind enough to tell us what size bore his fusils had, but his post traded with the French as well as the Indians, so they may have been as large as 20 gauge, or as small as 28 gauge.
A rifle that shoots a .490 ball is roughly a 38 bore, so you are getting ten more shots to the pound than the fellow shooting a .530 ball aka a 28 bore, and 14 more shots to the pound of lead than a person shooting a .570 ball aka a 24 bore.
However, it's probably more likely that at the beginning of the longhunter decade, that the rifles were around .54 caliber/28 gauge. If that is the case, then we are talking perhaps a 4-shot advantage over a 24 bore fusil. So the cost advantage of the ammunition is pretty nil at that point.
Then add the accuracy... a rifled pieces is much more accurate at 100 yards than would be the fusil, even if the fusil had a rear sight, but if the hunters are harvesting animals at 50 yards on average, you lose a lot of the accuracy advantage of the rifle.
As for the bag-mold... the advantage of the rifle is a snug fit between patch, ball, and rifling in the barrel, so the rifles were made with a mold to fit the bore. The bores of the time period varying a bit from rifle to rifle, a lot more than today, so to get that accuracy the owner would need a mold as store bought ball would likely not fit well. It is doubtful that the idea was for the rifle shooter to recover the ball from the animal for re-use on a regular basis, for if you have a load that will take advantage of the rifle's accuracy at 100 yards and allow you to recover the ball... that load will still blow through the deer at under 50 yards. If you do the reverse, and lower the powder charge to consistantly recover the ball in animals at 50 yards or less distance, you will miss or simply wound a lot of animals at a range near 100 yards.
So the cost per single ball may or may not have been that significant, especially when you add in the cost savings for the fusil vs. the rifle. Where the smoothbore loses badly is the cost of a shot load, and the amount of meat that load will harvest when compared to a single bullet from a rifle and the amount of meat and the hide that shot will harvest when applied to a deer.
If Morgan was having fusils shipped to him from his suppliers in Philadelphia, all the way to Kaskaskia..., then somebody was hunting with them. On the other hand, in Morgan's records documented in SOTF, Baker only notes only one fusil being used by one of the many hunters employed by Morgan. So the evidence appears to show that yes a hunter employed at a trading post did use a fusil, but the vast majority used a rifle.
So a person whose occupation in the 1760's was hunting, apparently would choose a rifle, either on credit or for cash.
Now as for other persons who hunted.., for meat on the table to supplement salted meat, or simply because they had no other meat source than wild game, a fusil might often be the gun of choice for those individuals as the cost of the gun might outweigh other factors. That's assuming there was a choice; assuming they had the access to both rifles and fusils for sale.
As for Virginia, and the area known today as Northern Virginia, there were a lot of riflemen in that region. Maryland's first two companies of riflemen in the AWI came from around Cumberland, and that is at least 5 days on horseback from Lovettsville, and probably closer to a week if not 10 days West of that area, so there is a good chance a man whose main income was hunting who hailed from the Northern edge of VA along the Potomac, had a rifle.
LD
