Yes, you should be able to get the loot of both enemy and friendly dead troops. The problem that comes with that is the fact the loot is possibly worth more than what you paid for the troops, and this can be exploited. I can see people starting to farm a certain troop that has good value (in terms of unit upgrade cost vs items value) and making profit by both killing your enemy and your own troops.
Of course, that being aware of this issue makes it possible to balance the looting system so that exploits can be avoided and depth to the mechanic can be added.
