I will share my experience for balance: I've been in game/logged in since the minute the game was available and pretty sure I've gotten twice as many roulette tickets than I have toes and fingers only to be awarded 2,000 and 5,000 credits everytime except 10,000 twice - no matter the reason for the roulette ticket or the number of stars on it. As far as progression, I am not rushing through the café cards (at 25 or the Euro Championship I think) having focused more on other parts of the game and repeating races to stack credits/try out different cars. I'm an old school GT car collecting grinder who absolutely can't stand games that throw cars and credits at you from day one as this devalues the game, shortens it's life, cheapens the rewards, thus killing my motivation for the way I play.... but you do earn the tickets so properly reward me for earning it at least 1 in 50 times). If things get better I will report back.
After looking around elsewhere for what others are getting, It would take some concrete evidence to convince me this is "luck" or anything close to a real "roulette" game, lol. Everything points at it being predetermined or at least "player X" is in one roulette category level of prize distribution while "player y" is in a different category level of prize distribution. If so, what determines this category? If you are playing GT7 in multiple accounts, what is the difference in which prizes you have received in different accounts side by side?
Yes, like someone already said, you can't spend real money on roulette tickets but after 40 times of not getting anything of value (and reading about people getting valuable cars and 500,000), it would certainly tempt some to go and spend real money for game credits, would it not?