It very much depends on the cost of the flight element with Thomsons, as the total costs with the package varies wildly. I have posted recently that the cost of our 2014 booking was £600 cheaper for four of us than it had been just 3/4 weeks earlier.
Prior to the Thomson reduction I was pricing flights from the midlands and booking direct with Romanza. The cheapest flights were Monarch from Birmingham for end of July, the price of rooms and flights was £2915 as flights were still expensive, plus getting a transfer sorted.
We booked via Thomson for £2371. Its a no brainer!
Ref the Thomson domination of the resort, they want to fill the rooms they are paying the owner for. This must be of benefit to the hotels ref food and drink and the other businesses in the village. Otherwise they may have lots of empty rooms out of peak times and fewer people spending money.
Thomsons latest tactic though is reducing the length of the season, this year they are only taking guests at the Romanza until early October. They have shaved 3 to 4 weeks off the season, giving the businesses less time to make the money needed to cover the winter months.