That's definitely a valid concern. > “Twenty per cent is a large sum of money, and if your competitors are avoiding the 20% you can’t compete,” Twenty percent

That's definitely a valid concern. > “Twenty per cent is a large sum of money, and if your competitors are avoiding the 20% you can’t compete,” Twenty percent is huge in retail trade. Many sellers have single-digit margins. Having a huge player engaged in such behavior on a massive scale means effectively eliminating all competition. They should compete, but on equal terms. They will probably still win, but at the same time contribute to the well-being of the society by paying taxes (just like everyone else).