This phenomenon is certainly troubling even for the Balinese themselves. If not acted upon, of course there will be more and more. One of the factors, according to tourism observer and lecturer at Warmadewa University, Denpasar, Bali, I Made Suniastha Amerta, is due to the application of the Visa on Arrival facility. Tourists can come at any time without being burdened with certain requirements, and will receive a visa at the Bali airport.
However, there are also other causes. Listen to this interview with I Made Suniastha Amerta.