Ultimately any market price depends of supply and demand, but the day we can send/recive/pay most people/companies with Bitcoin is the day we will have stable (and high) prices. Bitcoin will then have higher utility than Visa, PayPal, Western Union, SWIFT etc.
Suppose that you need bitcoin to do cheap money transfer, but you still need to convert them back to fiat money to spend, this will not help to stabilize the market price since you first buy certain amount and then sell same amount at the other end, creating corresponding sell pressure on exchanges
If bitcoin is the only money in circulation and enterprises use it to pay salary and purchase everything, then the utility of bitcoin will definitely help to stabilize its value. But it is not the case today