those sites have bots that track files from game sites like kongregate, gamejolt etc... there is little to do when this happens
but what you can do to take advantage of the situation is this:
-always put your credits INSIDE your game with a image and not with a text, it can be below the title in the title screen
-for .exe games, make the package separated; ex: linux version, windows version etc.
-read this tutorial: https://www.scirra.com/tutorials/860/si ... ame/page-1
-put information about where you upload your game, ex: this game is being updated on gamejolt etc etc, please download from there before report any bugs etc etc...
i think there is more you can do but you will lose your time if trying to combat this stuff, is better to think on creative ways to make ppl aware that this is your work and how to help then find more of it and support your work