"If they can afford to buy drugs, they can afford to feed their families," she said.
One man who had lost his benefit because of drugs had come for help three weeks ago.
"The only reason I gave him a parcel was because he had a little girl. If he hadn't, I would've sent him on his way," Mrs Walker said.
"We have to work hard to get the money to buy the food to feed these families, and I am not going to give it to bludgers."
Cases that involved children were different, however.
"The kids come first. We will never let children go hungry. Never," she added.
The welfare overhaul means sickness beneficiaries, solo parents and widows with no children aged under 14 face the same obligation to find work as the registered unemployed. Since October last year, solo parents have been required to work part-time when their youngest child turns 5, and full-time when they turn 14. Those with children under 5 have been required to take 'reasonable steps to prepare for employment' such as training and work experience.
Ministry of Social Development figures show 18,000 Northland residents collected benefits in March this year, down from 18,133 a year earlier. In the second half of last year 107 Northlanders had their benefits cancelled and five had theirs halved after failing to meet work-testing requirements.
Social Development Minister Paula Bennett said the new approach would offer people more individualised support, especially targeting those at risk of long-term dependence. The new work obligations for solo parents were an opportunity for beneficiaries to get back into the working world, she said.