How can a bunch of bits in memory be "pure evil"? If you eat french fries made by somebody who votes Democrat are the french fries evil?
Using Firefox doesn't support, or enable the viewpoints of the people who run the organization who develops Firefox. Firefox is free software, so you can use it without supporting its developers - unlike commercial products.
This was well-explained by FReeper stalwarts (many of whom had born on dates in 1999 and before) in several threads back in April. One such example came from from all-American Patriot fwdude who explained that "If even HALF of all Christians would ACT like Christians by having nothing to do with the works of darkness in this world, we could turn the culture around in breakneck speed."