More like disappointed. At 85% winning, it should have a better chance of it occurring; at 15% losing (as you would have put it), it shouldn't occur as that a low chance compared to the 85%, or are we doing Common Core Math now? Now, if it said 35% chance of winning (whereas it would be 65% of losing), I would steer clear from such as to me translates to a possible wasted ticket that could be spent on a better outcome.
Try to think in the opposite way: in all events you have a little chance of winning prizes (let's say it's around 15%), so it means that most of the time you shouldn't get them, and still you DO get the rewards, right? But here nobody complains, because this is beneficial for the player.
Try not to equate winning/losing with the chance of obtaining a prize. I never expect a so-called "rare" prize when I do claim; just only the mediocre ones. When I do win a "rare" prize that is of use to me, I would be "meh" as I keep that in inventory to be used when I need it. When I win a mediocre prize, I just go double "meh" as I either use it now or just leave it in inventory. Anyways, winning and losing are different animals; you either win (by higher chance of winning) or lose (by lower chance of winning); there is no other way. And, that's where that mechanic messed up, resulting in wasted tickets and no rewards/points gained.
The summer event just depends on who is active in your neighborhood and when can you capitalize (with some strategy) on getting the better prizes than them. In poker, there are 52 cards (not counting jokers), and if you know which cards were in play before the deck got shuffled, you will know when to either go further or just hold back until a new deck is shuffled; the same can be said for the wheel. Those who spun and landed on said prizes, those prizes are taken out of play, and the wheel gets "tightened" among the available prizes remaining. I have been in instances where everyone in my hood were spinning and taking out the "booby" prizes, and I just spun to win the best prize before reshuffling the wheel.