I started out as a speculator (I understand that most people start out like this), but I quickly realized how to use bitcoin to make my finances more efficient and a lot cheaper.
There is nothing cheaper when dealing with a high volatile medium of exchange such as BTC.
As for people happy with (any) fiat? The older generation experienced how all the fiat slowly degrades to shit and they are far from happy. Younger generations are facing the never ending recession and a lot of them live without any perspective for the future.
Bitcoin do not solve that problem...
People who do more than receiving their salary on a bank account also don't seem to be happy at all. I have experience with banking in several countries and in my experience, the main attributes of the old system are inefficiency, inconvenience and high fees and charges.
...neither this problem.
Bitcoin is the first alternative, with a completely new concept on money. I think it doesn't matter what % are speculators, it cannot affect the utility of the protocol. I don't think they are any ways harmful at this early stage either.
Finally, some sense. Yes, agreed.