Yeah the commander/troubled squad leader who needs an immediate remedy to a situation may become frustrated, but:

A) Thats war - you rarely get what you need, when you need it. remeber the old fasion video games where if you wanted to escape a tight spot, you would try to get someone on your team to manually bomb that tank, or actually take it out youself?

B) Think of all the people who just want to drive a tank and reign terror on the rebels without expecting an instantaneous death from above. Think of all the soldiers trying to work in coordination with eachother in a squad who dont want to all die because theyre too close together. Think of the children....

C) As Ive said before too many TTs flying around can distract the player from the actual gameplay. The game may become a Hide and Seek TT fight.