I don't know if this has happened to you much, but I usually play slots from time to time and when I get free spins I usually win something, sometimes more, sometimes less, but I always win. Today I got two rounds of 10 free spins playing Wild Bounty Showdown, and in the first one I didn't win anything, while in the second one I won about $0.34 (playing $0.20 spins).
I don't play slots, but it's not really unusual to read something like this about free spins, not at all. I feel like you're not supposed to get very significant wins on free spins for the greater times that you try, cause of course they're free!
But again, playing on the first 10 spins without getting even a cent makes it look even more like a time-wasting feature.
I am not a stranger to freespin from casinos, it is simply a way of saying thank you and please play more.
Exactly what I know about free spins. I also think most casinos offer you those type of opportunities when your balance has gone down drastically after a long play time. That can also serve as an Rtp on your entire initial deposit -- how ever, the algorithm doesn't run a lost business!