One possible excuse for plagiarism, they have hire someone to write it for them and they didn't know that the one they hire just copied it somewhere else. It is s a valid excuse? I don't think so. If they don't have any reason to scam then they should get someone competent or at least try to check everything because releasing their whitepaper.
Yes, it is possible. Now some ICO projects only want more investors, and do not want to do a good project seriously. If writing a white paper is just a task to prepare for an ICO, such this project also needs to be questioned.
And that's what they really do, to hire someone to write their whitepaper. Its not just a task, its a whitepaper, it was meant to show your project to any potential investors, then why don't they themselves wrote it so that they can present it clearly?
@eternalgloom - let's look at the bright side, we can spot them from afar, if they plagiarized other projects whitepaper then obviously a fraudster and scammer and not to be trusted by our hard earn money.