Correct type of shower handle to use for valve that sticks out too far?
What you are calling a white pipe is likely the body of the mixing valve. The installation as it is now looks carefully done: a nice circular hole, and a schluter kerdi seal around the hole (the orange plastic ring inside the hole). I wouldn't jump to the conclusion that it sticks out to much. You probably just bought the wrong brand of handle. 

You're best bet is to take this photo to a plumbing supplier and hope the can identify what brand of mixing valve you have.  Then you can order a handle and escutcheon (the cover plate) that fit your valve properly. I don't recognize the brand myself, I can only tell you it doesn't look like a Moen valve.