I have a large doubt that it would have a bad effect on the body. To answer your questions:

"What are all the teeth for in our mouth."

When you think about it, they're for juicing, and this juice combined with your saliva to make a "better juice". The teeth's design pushes the juice out of the pulp, and traps the pulp into the tooth itself. It's pretty amazing.

"Not properly chewing anymore?"

I still "chew" while drinking the juices :D I practice this more and more.