1 okw pays more , its not free truck cost fuel 2 okw does not have healing too(if ur response is sturm by ur logic usf gets free weapon upgrade cause the captains can buy them or already have them)
That is if we are talking solely about teching. This is rushing a unit we're talking about. Bumping okw fuel so they can rush a unit faster while ignoring the other bonuses included in their teching is Ludacris.
Also the sturm 3 aoe heals anywhere on the map is no comparable to a single weapon slot weapon. Not. Even. Close.
Crates are not the most effecient (well, 15mu to potentially heal your entire army only seems ineffecient because of brits stupid mega effecient healing) but the flexibility afforded by your starting unit being able to patch up your army on the front in undeniably incredible.