no GST for basics?

Some people say remove GST for essential or basic items to help the poor. I suppose basic items are things like rice, oil, sauces, bread, vegetable, fruits. However, even things like rice and oranges, there are cheap ones and expensive ones.

For example, the superior grade of a brand of soya sauce costs about 2.5 times more than the standard grade.There could be more expensive ones which I don't know of.

Then, healthy salt (contains some minerals but less sodium) costs about 10 times that of ordinary salt.

Poor people buy the cheap ones while people with high income, which includes foreign talents, buy the expensive ones. If you buy the expensive ones, then you cannot be considered poor.

No doubt the poor will pay a little less. However, a lot of tax would be not be collected from the rich.

So I prefer to collect this tax money from the rich to help the poor in other ways.