Ok, guys, solutions are allways better than complains.
If you find that this issue is anoying for you, solution is:
In units.txt, take out the capability to attack land from all of the air units you don't like to get down by infantry or something.
There is a line that states:
CanAttack: Land (or Mountain)
Take it out from bombers, fighter and whatever else you don't want to attack ground and instead just bombard it.
That is the solution. In fact, it is logic; bombers shouldn't be able to attack ground (attack meaning ala ctp2), instead just to BOMBARD it.
You're welcome
C-ya