First thing, bitcoin can't die overnight.
Second, people are getting crazy about all cryptocoins not only bitcoin so this trend might remain same if there will be no more bitcoin.
People are investing in bitcoin because it has limited supply and no any government can shutdown bitcoin network. People find it much safer to store their wealth in bitcoin than in their local banks.
Yes it can happen here. For example i am a investor here and i want to invest.my.money in a particular signature campaign and that campaign has a good platform that gets my interests but the campaign scammed me. And take my money. That will actually a disappointment for me and it can be the reason why some people loses interests here.