You can’t put everybody in tanks, as tanks are fairly helpless without infantry support. Even if they wouldn’t be, tanks need support personnel nearby on the gr

You can’t put everybody in tanks, as tanks are fairly helpless without infantry support. Even if they wouldn’t be, tanks need support personnel nearby on the ground for refueling, maintenance, and repairs. So, an army needs infantry. Infantry will, at times, encounter enemy tanks without sufficient friendly tank support. When that happens, things like these can be very helpful to bring antitank weapons to where they’re needed. The existence of such weapons also can act as a deterrence. The Panzerfaust served a similar role and was effective at it. https://en.wikipedia.org/wiki/Panzerfaust#Germany https://en.wikipedia.org/wiki/Panzerfaust#Germany: “However, the threat from the Panzerfaust forced Allied tank forces to wait for infantry support before advancing. The portion of British tanks taken out of action by Panzerfäuste later rose to 34%, a rise probably explained by the lack of German anti-tank guns late in the war and the increased numbers of Panzerfäuste that were available to defending German troops”