People seems to think that "pusher" can only play one style. That's ignorant!
I've seen a guy playing around 5.0 level (a vert good player with many tournament victories) and play like a pusher at times. He knows how to hit a winner when needed but he mostly try to hit the ball high. He has exceptional stamina and knows how to play net game (very good double player too)
I used to hit the ball hard before, but now I try to develop a "pusher" game because I find that hitting the ball high is a simple way to finish most of the low level players and still preserve most of my stamina, which is extremely helpful when playing in tournament.
When you lost to someone with good defensive skill and call them "pusher", just remember that Nadal also employ a pusher-like game at times to soften off his opponent.