what is the area of economics that dont work without bitcoin ?
None.Without bitcoin? Only area where privacy and freedom are very valuable.
You could at any time use Monero for them in that case.I think that all economics here can still work without using Bitcoin. expect, the companies are really related to BTC such as its exchanges or platform concerning with BTC 
This reminds me of the Euro, when it was first introduced and replaced a lot of currencies the only really affected were exchange booth, suddenly you didn't need to change marks into franks into pesetas and always pay attention to the exchange rates, there were done of them in the center of the large cities praying on tourists, now only a few survived.
Bitcoin is a currency, is not like some part of the economy will disappear if by tomorrow the $ or the Euro is no longer there.