Why is faceting not a common practice?

Because it take a lot of time and patience.  Most glassblowers prefer to work in the hot flame, then on a lapping wheel.  But when two people come together, the hot worker and cold worker can come up with some really cool things!

Is it worth it to buy terp pearls for your banger?

Investing in you is always good.  These are not necessary when you have a good carb cap.  But they are fun to play with, and how doesn’t like being a kid.  For pure function, you can do without terp pearls, but to enhance your experience they are a fun addition.

What could cause a base of a waterpipe to just crack out of no where?

Well, it could be that someone knocked it and did not tell you.  It could also be that somehow there was stress in the glass and it just released.  This is why glass should be anealed.

If a base pops off, it could also be a bad weld, but really we do not fully know why this happens.  If is different colors, that can happen from the different COE