Privacy is privacy - you don't know how important it is until you don't have it.

The main payment processors operate a mafia of sorts - it's a closed shop - tx fees are fixed and determined by them. One aspect of bitcoin is that is allows the person sending a payment & the person processing that payment (the mining pools) to negotiate the price. The theory being that transactions with a better tx fee will be included in blocks quicker than those that don't.

By freeing up these aspects of the systems we use to send & receive payment - you allow other forces to come into play.

What good is it to not let people know how much you make, how much is in your bank account or not wear a rolex in a ghetto? Tax evasion is not the only reason why you want your finances private.

>What good is it to not let people know how much you make, how much is in your bank account or not wear a rolex in a ghetto?

It helps protect the establishment and preserve the status quo. That's about it. It would be in most people's interest for these things to be public.