It is in talks with HMRC over its tax position.
I do not know what its coffee is like as I have never been in one, so I cannot boycott it, but it has done nothing "legally" wrong as far as I can see.
If there is any blame to be laid anywhere it is with our tax system. Some of the highly paid staff in HMRC should be looking at how it operates and report immediately to government. They should identify loopholes to be closed and avoidance schemes to be shut down, then the government can introduce laws to do so.