Prostitution is not illegal in Peru and this is purely a fanatical Christian sort of thing which the mestizos here like to take to even greater extremes than the people that exported it to them in the first place. It is in line with the other crazy things they do here like drumming in the streets and blasting away on megaphones about the "one unique path", etc... Most Andean pre-Columbian societies were quite sexually liberal so I am pretty sure prostitution was quite common even before the conquistadors came and did a good job of indoctrinating all their descendants. Can't say that things have really changed much though even with the ultra conservative Christian societal exoskeleton. With all the hypocrisy I wouldn't even be surprised if some of those whippers were regular clients beforehand that got riled up and had their "life changed around" by the orations of some priest. You meet plenty of these "switcharoo" types here.