Why are some relatives so shameless that they often go to other people's homes to eat without buying anything for free?

This is obviously eating and drinking.

If I meet people who eat and drink, I will stop this behavior in time. I must tell the man who eats and drinks that I have no money to buy food and rice. If you have money, you can give me some, so that I can cook and let you eat and drink in my place, otherwise we will all be hungry.

Be sure to let the person who eats and drinks see his feelings and let him retreat. You can use bad words to tell him that eating and drinking is laziness and cowardice.

Because their free food and drink bothers you, you can, then tell him directly, tell him jokingly at first, and only warn him if you don't listen.

Or cooking, she came to my house, no matter how I knocked at the door, I just wouldn't open it, so I shut her out. See how she eats and drinks for nothing and refuses two or three times. I don't think she will be so thick-skinned and shrink back automatically.