That's the whole idea of having 2 or more price points, because you have 2 or more types of customers. If you can only sell at 1 price point, I'm asking which one that is going to be? Or in other words, either as a company you start selling at a loss, or you lose your bottom tier customers.
If you don't understand this, there is no point in discussing this further.
What was unclear about "the proposed law wouldn't make multiple prices illegal"
As for what would happen in a competitive market with everyone acting in their best interest, I'm not sure what exactly would happen. But they're allowed to have multiple prices. It's not the prices causing the problems. And there are other ways to distinguish products that aren't artificial limits.
