Saying "At $60 I no longer demand vinyl" is exactly how supply and demand works.
Suppose there are 1000 people prepared to buy vinyl at $30 a go, of whom 10 are prepared to pay $60.
If you have 1000 records to sell, you sell them for $30. But if you only have 10 records and there are 1000 who would like to buy them for $30, you don't sell them for $30: you sell them for $60 each, to the 10 people who are prepared to pay that much.