Bacteria doesn't discriminate, and it certainly doesn't give a shit about your belt's honour or whatever it is people think washes out of it.
I have been asked by grown ass men why I wash my belt. They bring up the TMA hocus pocus about washing away your experience. They do so almost light heartedly, in a joking manner. Like they know it's silly, stupid superstition, but do it anyway. Like possibly spreading ringworm or staph is worth it for a minor chuckle.
My instructor once actually told me I shouldn't wash my belt after he had to reapply my stripes for the second time. He "scolded" me for it, again in a joking way. Like he knows he has no place telling a grown man and paying customer that they cannot do whatever they please with their own garments and laundry, but at the same time sincerely wishing I wouldn't. Why, to save him tape? I looked him in the eye and told him I was going to wash my belt once I got home.
It ridiculous that a culture can be so hell bent on sanitizing hands and feet, mats and uniforms. Use (questionably expensive) speciality detergents, shampoos, and soaps, yet engage in and encourage such a backwards idea as not washing the belt because of its magical properties.
