Ah, come on Puff that's not fair! Not only do I try and single engine taxi every flight but a CDA is always attempted.....even in the US. That and the energy saving bulbs in the Cod household and the daily wife beatings for having the AC on too low. Kids walk to school in the summer (12k round trip) and I make the gardener water my 3 acre plot weekly using only a watering can. Takes him 7 hours but at $1 a day labour pay, I can afford it!
Joking aside, contractually you have all utilities paid for by Emirates. UAE Nationals get subsidised rates so the Company can't really charge you as the threshold is different for them. Therefore, by default, you are being discriminated against. Wouldn't look good in court, even in Dubai. With the current state of affairs and shortage of drivers, I'd fight it.
Having said that, to be over the limit does indeed reflect an excessive use of juice! Maybe an offer to reduce by next month would be the way forward?
Harry