of course the price matters. it matters for the people who bought their coins. if the price is stable more people are willing to convert their savings into bitcoin.
Some people who had bought large volumes of bitcoin back in 2009 when prices were 10USD/1BTC are the real profit-makers. Imagine the profit they have made in 2016. Holding the coins is a passive income just because the prices are always bound to increase.
On the other hand daily trading is also useful as long as you keep eyes on the market and have some proper skills. All you need to do is buy at low price and then sell at high price, but make sure to get target prices since you never know how much really prices will fall or rise.