I also know of some horrendous activities by tour ops. Not Vision, the biggest ones.
1. Took an exclusive option on the majority of rooms in one (popular) hotel, at an agreed rate that was acceptable to all parties (I am not sure of the rate, around £9 pppn), take loads of bookings for the whole UK school summer holiday dates, then contacted the hotel days before the schools broke up, informing that the rate they were paying had changed to £3.50 per night "take it or leave it". Bearing in mind staff, food, drinks etc. had all been put in place, and the chances of finding other bookings in a few days were prectically zero, what else could they do but accept? Then the only hope is that the guests spend in the hotel bar or restaurant.
2. One of the very largest UK tour ops took an option on another hotel, but quite the opposite - not one booking was forthcoming. The hotel was (unusually) practically empty for the whole season. Imagine their surprise when guests from previous years came in to say hello, and informed them that when they tried to book the hotel, the tour op confirmed it was fully booked, and suggested another hotel along the road.
As they screw the last penny out of local hoteliers, they announce profits of billions - and one or two more local hotels face the very real prospect of going out of business. When people see this they often see it as a sign that Calis & Fethiye is dying, or unpopular - the truth is, multinational companies will, if allowed, kill Calis.