Mach tornado can be campy. Spaced fairs and bairs are also campy.
Camping doesnt have to be on the other side of the screen. It just means out of reach of your opponent. I camp with MK by staying in the area where they can't use melee attacks and if they use a projectile, i can move in and punish immediately.
Do not believe the generalisation that MK takes no mindgames. ALL characters require mindgames, and MK needs just as much as snake. You need to be a fantastic edgeguarder and pressure player. MK is all about making you're opponent make as many unsafe moves as possible. You need to read you're opponent so you can put them into unfavourable positions.
Here is an example:
MK dthrows Snake at the edge, so snake is starting to fall off the stage. Here are Snakes options:
Snake can jump striaght away and up B to recover high.
Snake can drop a little and then up b to gain super armor frames
Snake can jump for the ledge.
Bearing in mind the first part of Snakes up B has no super armor frames: MK can counter these by:
Waiting then Shuttle looping/Dair Snake as soon as the Up B comes out
Run off and Dair
Edgehog, followed by dropped nair
As a MK player, you need to know all these options. You need to be able to read your opponent just as much as they have to read you. As I said before, MK requires mindgames, otherwise people will take advantage of his light weight and kill you early, especially on the vertical.