Because we haven't got much more promotion or marketing to make it popular on bitcoin as cash . There are only people in bitcoin community to use it as cash. However, bitcoin is not still accepted from the government so that everybody is disquiet and do not get bitcoin as cash.
I have to disagree. We do not need more promotion or marketing. The Bitcoin community does not use it as cash. Most are just holding or use it very rarely. Some would like to but there is no place to spend Bitcoin. So what we need is to start using them. If i tell a friend to use this new form of money and to get on board, all he need to do is to ask me how often i us it and where and then i will have a hard time explaining why he needs it if he is not going to use it.