Altcoins were developed only so that people could mine on commodity hardware and it be impossible to mine on GPUs FPGAs ASICs... oh shit, why do they exist now?
Maybe it is time you take a strong look at Nxt! 
Not really, I was dissing them.
Regardless... there is an answer to your question...
Hence the drop of GPU support after 3.8. I agree alts are a side show, like clowns. IMHO they're only good for pump n dumps to make more btc
