Fred Olsen fuel surcharges - Are they being unfair again?

A few months ago I wrote a blog about Fred Olsen imposing gratuities on their guests automatically, (you can read the post here). I thought it was a bit unfair of them at the time but since then I've not hear much from them. There latest move however strikes me as really unfair!
A couple of my colleagues have blogged recently about the Fred Olsen fuel surcharges currently being added to existing bookings.
For those of you who don't know, because the price of fuel has risen so much in the last few months Fred Olsen have been contacting passengers who have already booked their cruise and adding a fuel surcharge to their bookings. If I'm going to be honest with you that's all passed me by a little.
Yes I think it's a little unfair that Fred Olsen are doing this to passengers that have already booked but it is in their Terms and conditions.
However........

I do think they're being really unfair in the way they've gone about applying it.
Most cruise lines apply some kind of fuel surcharge. In this day and age with fuel costing so much it's unreasonable not to expect it. Most cruise lines also have a clause in their terms and conditions stating that they can apply a fuel surcharge to the cruise even after a passenger has booked. Again a little unfair but again I think but everybody does it so Fred Olsen haven't done anything that other cruise lines don't also do.
What they are doing however is applying the fuel surcharge as a percentage of the booking. So if you've paid for an inside cabin you'll pay a much smaller fuel charge than someone in a balcony.
How is this fair????
How does this make any sense???
I suppose that if you wanted to get technical a guest in a large suite cabin might use a the tiniest more fuel than someone in an inside cabin simply because they have more floor space and take up more room but does it really matter how big your cabin is?
And why do guests with an inside cabin on deck five have to may more of a fuel charge than guests with an inside cabin on deck three.
Now I don't normally have a problem with the better off subsidising those not as well off as themselves, it's normally the fairest system but the way Fred Olsen are calculating their fuel surcharges is just crazy.
Come on Freds what are you doing? Why not just charge everyone one flat fuel charge like every other cruise line does?

Happy cruising