People are naturally skeptical about the novel things, especially when it comes to money. In order to stay safe, they tend not to touch anything that is related to them as much as possible. Afterall, why would you even try a new and haphazard system when the existing one is still functional? Lack of enough research and influence of the media are the major reasons that hamper wide acceptance of bitcoin. Some of them are just outright lazy to even think about adopting bitcoin(or any other cryptocurrencies in that sense). Some of these people will only change their minds once bitcoin has gone so mainstream, they can't even ignore it. I think it is not for you to convince them to adopt bitcoin. It is only with their own effort to understand bitcoin that they will appreciate what they are missing.