Household brands like Twitter, Google, Nike, Zara, Walmart, Ford and KPMG will IMHO pay. This is not binary, it is a continuum. Will TechCrunch buy theirs? Will AirBnb, Path or Zaarly?
It is a risk decision for these businesses.
For a relatively small amount of money companies are removing the potential brand and legal cost risk of not owning their .xxx. The more important your brand the more likely you will be to pay.
I totally agree with you that this is 'extortion', but just because it may not be right, doesn't mean we won't be affected by it.