HAMILTON retailer Maria Schuler sells synthetic cannabis to more than 300 people each day - 400 on Thursday this week - and said those who struggle with the drug need to "exert self-control".
She vows to keep selling the drug while it's legal because "you'd be stupid not to".
"If the demand is there, what can I do?" she said yesterday, after writing in a letter to the Newcastle Herald this week that it was "easy to sensationalise minority responses".
Last week three Newcastle people receiving treatment in a private hospital spoke of becoming addicted to synthetic cannabis.
The articles prompted emails from others experiencing similar problems.
Ms Schuler said synthetic cannabis was much stronger than traditional cannabis and "I wouldn't have it straight because it is strong".
She said people who had problems with the drug had "misused" it.
"If they had treated it right, none of this would be happening," she said.
Products sold in her store clearly showed a warning label that "misuse of this product may cause serious illness or death", she said.
"If you're going to misuse a product, it's not the product's fault. It's not the retailer's fault."
Ms Schuler opens at 6.30am. When she first started selling synthetic cannabis two years ago she opened at 8am.
"People would be waiting when I got there so I opened at 7.30am and they'd still be waiting, so now I open at 6.30am. I don't know how many people are using it, but they're from all walks of life. It's huge."
She employs a security guard on some days after incidents involving aggressive or desperate customers, but said some of her customers are in their 50s and 60s, and several use the drug because of cancer.
She is not concerned about legislation in 2011 banning seven synthetic cannabis compounds, or a NSW inquiry expected to report on further legislative changes later this year.
"If it's banned, it's gone, and I'll go back to selling cigarettes and tobacco products," she said.
"They tried to ban it once before, then the manufacturers changed the molecules and it was back on track."
Governments were receiving increased taxes because of her sales, she said.
"They're getting revenue out of this one. My GST has gone through the roof.
"Look around you. I sell cigarettes.
"Synthetic cannabis is the same. Is it healthy? No.
"But it's legal, and it's the same deal. I know it's a grey area, but it's legal, and available, and the demand is there."