If the drugs are as safe and well tolerated as claimed, then its users should be able to hold up to all the responsibilities of non-drug users. No getting off or reduced penalties for otherwise crimes because “they were under the influence.” If someone isn’t able to pay for their own food, lodging and other ordinary expenses they shouldn’t be irresponsibly wasting money on optional recreational drugs and thus shouldn’t receiving government handouts. Now if private charities wish to provide support for druggies they are free to do so, but public charities should at least try to avoid that and have mechanisms for booting druggies off the dole. Although the drugs may be presumed legal for adults (juveniles may have different rules) the judicial system should have some mechanism, whereas with due process, someone who’s proven through serial misbehavior, that they can’t responsibly tolerate this or that drug should be able to be legally barred from using it, with the kind of penalties previously applied to all for use pre-legalization.
I’ve already covered that in an earlier post here when I said drug tests should be considered for welfare recipients. By far the vast majority of marijuana users are self supporting members of society contrary to what you may think.