Every person who sells their productivity for Bitcoin and does not immediately spend what they earn is contributing to that ~$1.3 million/day requirement.
This will be the key to a major price spike in my opinion. The more people are paid in BTC for services, employment, etc. the higher the price of BTC will go.
Miners hoard a lot of coins too. Bitcoin companies accumulate bitcoins and their owners do so as well while they pay in bitcoins for time and services.