Fear from hacking because if all of your money are now cashless it is prone to be hacked by someone and worrying this money will not return back to you.
The main issue is that people do not want to know about how the online wallet works but want to have this facility. If we take a little tutorial before adapting to online wallets, we can stay safe from the hackers around the world. Some people have their passwords so weak that even the person who knows nothing about hacking ends up hacking them. Knowledge about the security of the online wallet system is really very mandatory if you want to save yourslelf
Cash is more reliable and secure than digital money and that is the main reason that most of the people fear from cashless world. Everyone satisfies when he sees his money in hard. He is mentally relaxed and digital money cannot be seen and one has the fear of being stolen and hacking.
Computer and internet is not a security guarantee and thats why people are afraid of digital currency. No one can give surety of a secure bitcoin wallet.