Those revenues are peanuts compared to savings for:
Less prisons
Less prison staff
Less cops
Less judges
Less bailiffs
Less public defenders
Less court buildings
Yes, but because of the legalization scheme, drug criminals have entered the legal market as licensed sellers.
more drug rehabs
more ER visits
more deaths due to weed induced accidents
more nurses
mored doctors
more hospital beds
more bus/taxi/train/plane accidents
more crime
more violence...
And hopefully this will lead to lower taxes, especially for the middle and working classes and small farmers.