Dh and I are both teachers ( well I am taking a year off as we have a baby) in an international school outside of Cairo. We were both given an expat package, I have never heard of schools only offering the expat package to one half of a teaching couple. I would certainly not work at that school.
But if you move somewhere and then one of you looks for work, you will be offered a local package. If one of you has all the benefits, ( medical insurance, housing, schooling for dc's, flights) it may be doable. It would depend on where you are.
Our life here is much better than it was at home (ok it was better with two expat salaries, this year is a bit more like being at home) but I know it will better again next year.
As the developing world is so inexpensive, we save money as well as enjoy life. We have way more disposal income, holidays, meals out, a cleaner, we are members in a private club that has playgrounds, 4 pools, restaurants and loads of space dd to ride her bike / scooter.... general much more fun and time to enjoy life. Yesterday we went on an hour long fellucca ride on the Nile, for less than £5 total ( there were six of us, the boat easily would hold 20)
In Egypt, we would be looking at about $5-600 US a month for a nanny for dd2, so also much cheaper than home. We could never save on two teachers salaries at home.
One thing I recently came across was getting dc's to school. Dd1 goes on the teachers bus with DH ( we are driven to and from school) but I have many friends who teach at another school which does not allow children on the teachers bus. One mom takes her dd in a taxi every day, I am not sure what others with school aged children do, as teachers leave in the morning before the kids. I guess they need to get a car.
Overall it has been a fantastic experience, we will probably be moving to Asia next year for a few reasons, but I highly recommend teaching overseas. One problem we have is feeling obligated to go home (Canada and the UK- so extra flights) for all our long holidays. I have already told everyone that next Xmas is for us, and to only expect us for home half the summer! it's hard when kids, there is the guilt about depriving the grandparents!
Feel free to pm me if you want - dh is a total researcher!