People are creating Bitcoin forks simply because it's the latest trend. Since it forks an already existing economy (the bitcoin one) it profits by making everyone holding BTC part of these fork's economies as a direct result of the split, since everyone holding BTC, gets whatever forked coin in equal amounts at the time of the split.
People may support it because if the fork gets support for a while, it will get listed on big exchanges, therefore it will pump, and people will be able to dump it for more BTC.
It's exactly like the ICO mania. Do you believe in the technology? "No. But it's free/I'm going to profit";
It all started with Bitcoin Cash and here we are with 2 new shitcoins in less than 2 months (Bitcoin Gold and Bitcoin Diamond). I'm just waiting for Bitcoin Copper, Bitcoin Emerald and Bitcoin Moon.
Don't you think it's quite weird seeing coins like bitcoin gold, bitcoin diamond? And wat actually fork is, is it a way to create new coin, or it's side effect on bitcoin's system changes?