[Edi]

The flagellant issue could be and probably is a feature. These are, after all, religious fanatics who are more than likely drawn from the ranks of the destitute who suffer from all sorts of ailments and injuries. Being a flagellant probably beats starving to death in a gutter and the shared religious fervor and promises of rewards in teh afterlife would give their life (short as it may be) meaning. That's how I see it anyway. At least it is a logical explanation.

Edi