The dark web is the World Wide Web content that exists on darknets, overlay networks which use the Internet but require specific software, configurations or authorization to access. The dark web forms a small part of the deep web, the part of the Web not indexed by search engines, although sometimes the term "deep web" is mistakenly used to refer specifically to the dark web.
Every affair in the dark web will use Bitcoin as a method of payment. In the dark web there are various illegal businesses such as the sale of illegal firearms, drug trafficking, assassins and hackers.
What are your thoughts on this Bitcoin abuse?
I think it's possible because bitcoin is decentralized, it's possible to be used in any transactions such as payment for drug trade, extortion, and other criminal activities. Bitcoin and other cryptocurrency transactions leaves no track, so it's safer for them to use it in their transactions. It's one of the best characteristic of bitcoin but somehow it's a little bad because other people take advantage of it.