Different people have different preferences. Just like how some people prefer to use cash when dealing, some prefer debit card, some credit card and etc. Each method have their advantages and disadvantages, but people still use them. Same argument for bitcoins.
In fact people know the importance of bitcoin, bitcoin is no doubt need of the day and its importance is increasing form time to time, that is why only wise and intelligent people will like to invest money in bitcoin, because they know that still bitcoin has a very potential to its price to increase. and hopefully very soon they will see a good increasing in bitcoin value.