Actually, the top tier income tax rate for high earners is pretty close now.
The 80% tax rates are pretty much over in Sweden. It was in the 1980's that Astrid Lindgren, author of the Pippi Longstocking books, started their tax revolt. Her income tax one year ended up being 110% of her income.
After the revolt, which shook up the government, tax rates and social benefits really declined.
I'd also be willing to bet you that locking up all these drug-monkeys costs more per addict than Sweden's social programs. You'd also have to add in the expenses related to the high drug related crime rate which could be reduced. Have the government sell it, tax it and turn back part of the profit to drug rehab.