No. Most wealthy people don't evade, they avoid.To be technically correct, it really is evasion when the purpose is to violate the spirit of the law. Which is, very very simple: wealthier people paying more taxes is supposed to have the net effect of benefiting more people. This makes sense and is a good idea because in a business's quest to "maximize shareholder value" it tends to use more than its share of resources at the expense of many who are not shareholders.
Think: more WalMart 18-wheeler delivery trucks driving on roads wears down roads more quickly, and creates more pollution for everybody to breathe, regardless of whether they are a WalMart shareholder.
The original tax code was designed tax business only -- individuals didn't have to pay anything for income under $4K (adjusted for inflation this is about $100K today). source: http://books.google.com/books?id=ogUNAAAAYAAJ&printsec=front...
Instead, the evolving nature of the business loopholes (driven primarily by what boils down to real estate exploitation) means that wealthy people still pay a "tax" (that is, they don't technically "avoid" it), but it gets distributed to fewer people -- the lawyers and accountants that cost a fraction of the value they deliver you cited being the first in line.
Now their incentives are to maximize the theft from the people, because in doing so they get a cut of the wealthy client's wealth. That's probably a crude way of putting it, but it's the basic idea. A few people catch a glimpse of this right out of school (me, ~11 years ago) and make a conscious choice to not sign off or embrace the ethics of those kinds of people or companies (and to be fair, most of them didn't want me either). There were quite a few really rough years.
Anyway. Digression aside, the IRS is pretty much the only entity that has the explicit purpose of discovering, investigating, and recovering that theft from the people. The tax system is not bad and the IRS isn't either.. it's the matter of how to best spend the recovered funds that probably needs re-hauled.