I think bitcoin's price matters all people, not only trader. If the price of bitcoin is high it will attract people to start using bitcon, because the price is high and good for investment.
If the price of bitcoin is high, I see most of the newly engaged in the bitcoin world will not have the guts to buy at that "high" range of price to make it as an investment.
But on the other hand, it will make them boost their efforts and work to earn bitcoin from doing other bitcoin earning method without the use of their fiat money.