Though the guy is an obvious charlatan, there is also the issue of local cultural practices and the beliefs they are based on that are then injected into such a context: this where such a thing would be acceptable.
They are taking the guy to be a holy man.
John9:
6. When he had thus spoken, he spat on the ground, and made clay of the spittle, and he anointed the eyes of the blind man with the clay,
7. And said unto him, Go, wash in the pool of Siloam, (which is by interpretation, Sent.) He went his way therefore, and washed, and came seeing.