In mabinogi, unless you're constantly in a party, it is mandatory to purchose pet to enjoy the game. I have 4 char and over 12 or more pets (with custom ai) in that game. But to be honest, I had no problem investing in Mabinogi when it first launched. The rebirth card was hardly a reason for me to dislike the game due to the drastic benefit and it was not really require.
Onigiri isn't really P2W, but it does have a feeling of desparation for income. I can't really say I'm encourage to invest in Onigiri. There is also the fact that some of my closes friends and close gaming friends were curious to try out Onigiri since I was playing it, all uninstall the game the day after saing it does not feel like a game they see themselves still playing in the future and telling me to wait on Archeage instead. Friends I've made in the game, seem to vanish as well. I do see myself playign the game solo casually though.