I'm fairly new but the free credit system is in general a joke. I have spent money on the game and will again so I have no qualms trying to get some free credits.
I have no issue with ones that default part way through to the 5 credits. The ones that bug me are ones that you get all the way through and then they go to screen which says it will be up to two weeks before were credited. How about never. Oh and the ones that stop midstream but don't give you the 5 credits.Others are identifiable early that they won't give you anything no matter what so I just click off when I recognize.
As I said im fairly new and this is just a rant. Probably way it has always been.