Everyone knows that it will probably go up, but when you hit a life changing price target, you'd be mad to continue taking 100% risk.
Everyone knows that holding dollar, euro, yen, pound and other fiat trash is nothing else but taking 100% risk. It is not just risk. It is stupidity because it is a sure loss. Holding bitcoins is the most successful escape from that risk!
Unless, as you say, they want very much to buy something tangible like car or house. But make no mistake! This car or this house will be the most expensive house they'll ever see throughout their entire life. For instance, I know people that sold their bitcoins at 750 euros to buy a bike. At that time I warned them that they're buying the most expensive bike they'll ever see!

Its like that game "Deal or no Deal", the best chance of a high return is always gained by going to the end and never swapping your box. But in reality its not always the best decision.
Another example, lets say you are fairly poor, and I gave you $100K, but said your could win another $200k, on a 50/50 coin toss (Giving you a total of $300k if you win, $0 if you lose),
I don't think the decision is so easy.
Your life is finite, so money now is sometimes better than a chance of more money the future, you just have to assess the amounts, probabilities and risk you want to accept.
You're missing something very important!
Bitcoin will change not only the world of Finance. Bitcoin will change the world of Consumerism! It will change how people think about what they consume! "Do I or my family really need this?" With Bitcoin there will be no more inflation to pay for your mindless consumption and seduce you into debt enslavement! With Bitcoin there will be heavy consequences for every consumption you don't really need! And that is excellent because planet Earth right in front of our eyes is rapidly turning into one giant waste dump!