People usually have negative thoughts about everything outside of their knowledge.
You friends are kinda right about bitcoin.Was it used in the deepweb(or darknet) to buy illegal stuff?Yes,it was.Is bitcoin a scam?Hmmm,who knows?What if bitcoin is just the tool used for the biggest exit scam in the entire financial history?I'm not hating on bitcoin.It's just a different point of view.You have to know and understand the point of view of your friends.
Yes I agree, its normal of people thinking about bitcoin and how bitcoin's usage for our financial life. They directly judge based on the negative side of bitcoin without knowing the true benefit of it. But, we still make it sense just to wait a little bit and im pretty sure that bitcoin will be more popular than before and finally many people can realize how true the bitcoin is.