Theiy are not British Gas

Ecotricity are just beginning to roll out 'green' gas (ie produced from 'native' British waste). And they have been harassed by British Gas -can you believe it? Here:
We are not British Gas | Energy | Zerocarbonista: "first alleged that we were ‘pretending’ to be British Gas. They didn’t like our tongue in cheek “Real British Gas” logo it seems – we’ve tweaked it a bit here to make them feel better. It’s hard to take that seriously – we are so not pretending to be British Gas. Why on earth would we? It was a joke guys. About a week later we got another legal threat, this time dear old BG claimed we were misleading people by offering Green Gas, when in fact it wasn’t (green)."
Now why are they so rattled by a minnow? Clue could be in the rest of the text ...