@Treyon:
You got that wrong.
The hunter guild demands "only" 70% - they probably have a deal with the nobles / government for that.
Before the MC joined the hunter guild he had to pay 90% (40% to the local governor and 50% to the state / who ever rules the country).
So joining the hunter guild is actually beneficial compared to not joining it.
The real question is how the author comes up with such ridiculous numbers.
If you really got to keep only 10% without a guild and 30% with a guild membership then people would NEVER report their hunting / monster slaying success.
They would sell it all on the black market without paying anything.
Furthermore no one would be willing to help the lord or whatever when they need help for anything (like a local hunter searching for their prey) because the workers would be taxed again for whatever they earn.