I Do not know why they keep on popping. The question is how will these forks affect the bitcoin market. with these upcoming forks bitcoin's price may fall back to 10K or maybe 9K depending on the support that people will show with these coins. Still there is nothing to be afraid of since bitcoin's price will just have a correction but will rise back up. good thing for traders.
I don't have any idea about these forks. But i think December is a Month for bitcoins . A month when the price maybe increase much more. So the goal is increasing the bitcoin's demand. Since investors like to buy when the price is low. So maybe that's the main reason why so many fork coming in this 2017.