I'm not trying to disagree with you, just provide some context that this is normal human behavoir and you don't really need to be getting mad about it. Sure, by all means put a stop to it now and forever going forward. But no need to stress yourself out. And yes, if you have a big parcel of unposted, unattended woodland, people are going to hunt on it because it really isn't hurting anyone or causing any harm (if done respectfully).
But listen I basically do fully agree with you - its quite disrespectful to trespass and hunt without permission. When I bought my property, I had to deal with this same problem for a few years. My parcel had been unattended, so dirt bikers had carved some trails into it, and (the same?) people hunted on it freely. Shotgun shells everywhere. So I posted it, and blocked off the access trails. They chainsawed my blocking logs, and tore down my posted signs, and left garbage a few times.
This was one of the reasons that I intentionally allowed a grizzled buddy of mine to set up and hunt my property every fall - he ran a couple people off, took down a couple random stands, and after a couple years, no more problems. The dirtbags finally accepted that this property was now private and off limits.