I don't think it is moral to outlaw a new technology just because some criminals are using it. There is nothing inherently criminal with the technology. Similar to nuclear, guns, computers, cars, anything. Someone is always going to sharpen a stick and use it for murder. Should we assume that everyone who collects sticks is a murderer, and therefore we should outlaw stick collecting (enforced by "good" stick wielders)?
If you object became more criminals are using it, then we simply need to promote its use among B2B and B2C. A trustless and decentralised electronic currency is surely a freedom-enabling idea and should be promoted. It has long been the dream of cryptopunks and cryptographers.
Lots of crime is facilited by, and done in the name of fiat currency too. BTC can limit that. It's just a currency and one consciously designed to avoid the inherent flaws of fait.