It would be unlawful for prices to be "controlled".
The pattern is simple. The new years model is announced around May, goes on sale August/September. Everyone wants it, demand is high and retailers can sell them easy, and there is no incentive to sell below RRP.
Come May the 2017 model will be announced, and despite not being available yet people will want the latest paint or bling and will wait until August/September, so retailers then start discounting to keep the existing model shifting out the door.
By typical retail standards the mark up over cost is generous if sold at RRP, but still not to the degree that a Rolex or Aston Martin would be. Giant, for all that, are still extremely competitive on the market for & spec, and the profit goes towards a huge R&D machine that gives us cutting edge technology and some superb bikes. It the likes of Spesh and Giant that push the market forward in terms of prices features, model development. If it were left to the like of Rubble or Dolan, who simply punt on off the shelf frames to the buyers choice of spec, then development would stagnate.