I think you are missing the point though. I won’t try and speak for the others, but to me my thinking is: Burning a million quid (is a quid the same as a pound?) is stupid and wasteful. But, it’s their cash, so have at it. What gets me (and I’m assuming the other people who have chimed in about this) more annoyed is the people defending it as art.
That is, the burning of a million quid is merely stupid, and that’s that. People defending it as art is annoying and I feel the need to say something about it. So, if their intention was to shed light on how the art world will defend any silly act done in the name of art as artistic, then I guess they succeeded.