The flaw that is raised isn't that BTC is used to buy drugs, but that it (in the view of those raising the complaint) doesn't have a strong use aside from buying drugs (and, while "drugs" are usually mentioned, the substance of the complaint appears to be more about drugs-as-popular-form-of-contraband rather than drugs-qua-drugs.)
And given the way governments tend to respond to things that (1) are primarily used to facilitate unlawful trade, and (2) become increasingly popular, its a real, if political, risk for the Bitcoin ecosystem.
And? Even if that was true, I don't see the point.
A large portion of internet traffic, quite likely the majority, is transporting porn or "stolen" movies.
Should we now condemn IP because it's mostly used for such despicable activities?
The point is in the paragraph after the one that you quoted a few words from the middle of.
Other than it being illegal? Nothing.
But you're right to point out that, in sheer usage, Bitcoin really has nothing on the USD when it comes to buying drugs. Still, when you're asking why anyone would consider buying drugs with bitcoin to be wrong, you have to understand that not everyone considers that to be a positive or even entirely neutral act. Most people consider a currency whose primary use case involves breaking the law to be a net negative for society.
Most european governments do. Germany, UK, Spain, Italy etc. include revenue from drug trade (and prostitution) in their GDP.
Most people consider a currency whose primary use case involves breaking the law to be a net negative for society.
Do you really believe any law would be broken any less if Bitcoin didn't exist? Should we also condemn BitTorrent for the same reason?
What's wrong with people using BTC to buy drugs?
How is it better or worse than people buying drugs with any other currency?
Why is it "bad" for Bitcoin to be useful and first adopted in that niche?