That is the point, the market will find the equilibrium, which is selling bananas at a market clearing price ($0.50) and make a modest profit on each banana. You can charge $150,000 per banana, but Bill Gates can just go to a different banana stand OR just not buy a banana and now you make nothing.
I'm not talking about charging 150,000 per banana. I'm specifically talking about charging Bill Gates 150,000 for a banana and charging you 20-50 cents.
If I knew how much each customer could pay[1], I'd charge them exactly that.
1. At profit.