Money can evaporate in the DXB heat. Every time you go to the grocery shop another couple of hundred dirham disappear. When you want to get the family out of the house, it will cost you. Especially in summer, when it's too hot to be outdoors. Some wives and kids head back to home countries over the summer holiday break. Not cheap.
Every holiday you take is an overseas holiday. Take more than one (your leave will be given in multiple groups), and your up for tickets, travel insurance, accommodation (staying with family/friends wears thin as years pass). Not cheap. As a new joiner, your staff travel onload priority for discounted tickets is low. Flights are normally full. This means expensive firm tickets, or full fare tickets to ensure you and the family get to travel.
Once the children start school costs go up a lot. Most of the school fees may be covered, but you will still be left with the final Aed4000 to 7000 per child to pay (10% the company let's you pay so you feel you are contributing). Then there are uniforms, and a constant amount of other costs that all add up, excursion here, after school activities there, etc etc.
When you do get a chance to be home and take the Mrs out to dinner. You can dine at nice places that will give a good discount. But even then, the bottle of wine will set you back $US 50 to 100 for the cheapy.
I saved very little as an FO. I was lucky that we received profit share each year, and that paid off all credit cards. And I had no car loans etc. That was a while ago, and salaries have gone up since then, but so have the prices.