Sundays are when you are given your allowance P5000 and you can go to the market.
And, even then, the most noticeable distinction is in the look of the tails.
Sometimes I'm all on top of perfecting some stupid graphic, other times I'm 'screw the graphics! But by presenting it all of the options they unintentionally trigger all of the evolutions at once! Ailments can all be inflicted through various environments while playing, but all have a 10% chance of being inflicted, normally.