When CERB came out many people who had broken their addictions were targeted by dealers because they suddenly had $2000 of free money. If they had only $300 to $500 per week, they would not such attractive targets. If the money was deposited in their checqueing accounts, it would be easier to buy food and other stuff than it would be to buy drugs. It would not stop people who want to buy drugs from doing so, but it would help those trying to escape drugs.
For people who lack housing and, therefore, probably bank accounts, appropriate agencies could secure addresses and bank accounts with provision for payment for shelter being the first expense each week.
If we start with the goal of helping each person as they need to be helped, we can find ways for basic income to be helpful for them.
I would amend the banking act to require financial institutions with personal chequeing accounts to provide low cost chequing accounts for people with incomes under $50,000 that include debit cards, a few counter cheques each month, unlimited point of sale debits, and five withdrawals per month for less than $5/month. Fifteen years ago I got a better account than that free just because I was 60 years old.