True for anti material but for a rifle and ammo for that way cheaper for other deterants as vehicles are not able to move through certain terrain and will mostly stick to water or roads. air you need more than a single round per trigger pull weapon and well beyond range of most rifles.
That is why ied , rpgs where used against troops cheap and effective. Rpg has range of 950m but accuracy sucks after 250m the training rounds are loaded with standard AK ammo.
Still at 250 it’s close and engagement will happen as it’s not subtle and leaves too big a trail to not be seen. Plus where do you get one with ammo here not at local gun store. In Africa the price was around $600 for launcher and between $60 and $200 usd per rocket.