"Right now it is raining methane on Titan. The planet Uranus is, hilariously, orbiting the sun sideways while Venus spins backwards. We sit here on a planet marked with collisions, rocked by earthquakes, shaken by storms. A planet doomed to be fried in radiation as its magnetic fields collapse, until the sun grows and leaves nothing of the earth but dust. Here we sit, glasses on our noses, inhalers in our pockets, braces on our teeth, and we say "Behold the perfect ORDER of it all!""
As for Mario Kart? Each game does play differently aswell. There are different things in each game to differentiate themselves.
Double dash? There was the whole tag team thing. Mario Kart wii? Bikes, tricks, the whole style of play with the wii, and the lack in an invincibilty frames after being hit makes the wii one play differently. Mario Kart 7? Added customization to make your own karts and the changing type of karts as you progress through the stage (like gliding for example)
It's often the different styles, but similar styles, what make it different. Like the inclusion of the spin dash of Sonic 2, while at first seems minor, but it seperates itself from the first one.
Your post is full of fail.