You might think that, but I have seen it several times, and many years ago it happened to me.

I was landing a CGM Chipmunk on a grassy field, the grass was "Clumpy" and shortly after touchdown, the gear hit a clump and the plane nosed over. No damage done, but the abrupt stop caused the clunk to swing forward. I couldn't figure out why the next 2 flights deadsticked, until and older and wiser clubmember suggested what might be the problem.

Removed the tank, and there it was! The clunk was stuck up in the neck.