I agree with you about the cigarets, alcohol, junk food and other stuff, (though most of that can not be bought with food stamps or vouchers anyway.) When you're talking about cash assistance, that's a tricky thing. It would be hard to create a system like the one you're talking about and it likely wouldn;t be very cost-effective.
But I do believe that food stamps should cover things like soap, tampons, toothbrushes, toilet paper, and other hygiene products. I have a friend who used to survive on foodstamps because he was low income and all of his money went to supporting his daughter. He could barely afford his rent and the foodstamps were the only way he got to eat. But we were always buying things like toothpaste and soap and laundry detergent for him because he had no way of affording it and he wouldn't keep his job if he couldn't be decent. I really think that people who survive on that kind of assistance should be allowed human necessities like that.