PTC = HYIP.
I've myself lost $15 by buying a package on a ptcgen website that turned scam after being online for 6 months.
I earned a lot initially but just managed to earn back my investment without any profit and hence it was a total waste for me.
Just because you lost money from one of the PTC websites, it doesn't make the whole PTC industry a HYIP. It was your bad selection, there are still many PTC websites as I said earlier which won't scam you, ClixSense, NeoBux, etc. But, would definitely at some point you'll feel that you are wasting your time.
Again I'd say, very smart people can live their luxurious living with PTC websites. I know the names of few.