For those who are sure to do, let them explain everything to them, yes it is difficult but they need to go through the big talk or prove to them that you really are paying a bitcoin and that's not a scam, maybe we're not obligated to understand more about bitcoins are ashamed of how and what they are, but because this is the only best way to do it for the future learn how to keep them silent, and it's better to learn how to use bitcoin