It's kind of a pity that three years have passed since it arguably went mainstream (among the tech literate at least) and the most prevalent use case is still by and large speculation. Making money is cool and all but the technology had a lot more promise than this.
What? Living in a country with a broken financial and banking system I'm relying on Bitcoin for storing and transferring value. Check out Bitcoin search trend for South Africa, North African countries, Pakistan, and Venezuela.
Other reasons to use bitcoin: Drugs, Money Laundering, CryptoLocker, Capital flights, etc...
Up until this month - most of the speculation has been dead. That's why coinbase is pivoting. The majority of bitcoin is being used by people who need it in order to run their businesses.