All lower case, and multiple periods at the end of each sentence, a 'tell'?
So called - free credits - are in fact paid for by the advertisers when they pay WGT to have their video's and surveys available on WGT.
The advertisers likely pay in several times more than all of those who buy credits.
Those members that watch the video's and answer the survey questions to get the 'free credits' are the main reason the advertisers use WGT,
Without those advertisers, the 'buy all my credits' crowd wouldn't have any where to buy credits, because WGT would no longer exist.
No doubt though, WGT makes it real hard to think of them as being very user orientated. It seems like they insist on using the Netflix model.