I hope sharing bath towels isn't a thing... Although I admit a bias: I came out of a family that had a strict policy of 1 use per bath towel before it was washed.

But yes, this article does sound like they think towel sharing happens. Especially with lines like this:

So if you have multiple family members using a towel, then on the third or forth use it needs to be washed. This goes for hand towels, too.