I found that this game can be fun if you play it very casually. I used to get frustrated when I would get nothing valuable upon spending tens of rubies on a pipe, in one case even uninstalling the game afterwards. Since it seemed to start getting more generous at one point, I said "Eeeeeh" and gave it another shot; it is Mario Kart after all, and one with tons more updates than any previous game in the series.
Yet, I can't help but think that there's still something fishy going on behind those pipe probablities. See, I had four pulls worth of rubies and decided to use them on the recent pipe with 9 Mario spotlights, which make up about 12% of appearance rates in that pipe--pretty high if you ask me.
My first three pulls gave me almost complete rubbish, except for a Mario Hakama duplicate (from a green pipe fake-out no less) and a couple other High-End non-spotlight units. Then, on the fourth pull, I got--no joke--FOUR High-End Mario alts that I didn't have, back to back. It seemed very improbable that they'd show up so concentrated in a sea of disappointing stuff.
I've heard this rumour that the game might make High-Ends more difficult to obtain when it detects that you have only used F2P rubies thus far, but I don't have any solid information to back it up with. On the other hand, to give some empirical examples of the game's generosity, there are Special Pipes, the Token Shop and the Tier Shop which provided me with many things I didn't have, not to mention that I got Builder Luigi and Party Pauline from free pipes.
