Because it bio-accumulates and doesn't break down, and there's no way to remove it from entire aquifers or a huge chunk of land and the stuff is still leeching into aquifers?

How are small towns supposed to pay for these treatment processes? How are individual home owners, since in many areas everyone is on a well?

What are all the marine critters (and everything that eats them, and everything that eats those critters, etc.) supposed to do?

All so McDonalds can make a Big Mack container that doesn't get soggy?