Easy way to develop games!!!

Hey friends!!! I am game developer and recently i was just finding something related to games and i came across some of the websites which can give you readymade sourcecode for games.

We just need to do download that sourcecode and replace the code with our images. Below is the list of sites:

  1. Buy and Sell Apps and Games for iOS and Android | Chupamobile
  2. iPhone App Source Codes | Buy Mobile Source Codes | Android Source
  3. Buy and Sell iOS App, Android and 3D Games Apps Source Code - Sell My Source Code
  4. Sell and Buy Full source code of iOS/Android Apps and Games

But i have question that anyone tried game developing this websites…??? If yes then tell how it works and is it beneficial to use it.