...and the so-called "war on drugs" gives them every opportunity.
It is a natural tendency of bureaucrats to move towards tyranny, and that is a separate issue from any vehicle they may use along the way.
The abuses are just as grievous within game warden laws, and those preceded the drug war by generations.
Embracing a drug culture would not in any way slow abusive government down, they would just throw more troops into military raids on Amish milkmen.