So is walking stuka.
- It is more easy to hunt down a StuKa-zu-Fuß than the Howitzer, Howitzer can be remaned.
- Howitzer often double-shots a support-crew, same StuKa-zu-Fuß. BUT Stuka-zu-Fuß often only killes 2-3 men of a crew per shot, which means waiting for cool-down. Howitzer is cheaper and does even that job better for what it is. (same problem is the Katjusha/Panzerwerfer paradox).
It is funny to see, how often you try to defend broken mechanics. (edit: it doesn't depends on the fraction, fan-boy free talk. But it seems you don't get it)
Start mod-tools, replace leIG18 with Howitzer and start playing. Fun-fact, you are able to neutralize the popular HMG/AT-gun combo with ease.