The link provided by Bill D provided more information than just the average salary ($34,000); if you scroll down, you see concrete examples of some of the highest salaries for specific job titles.

It is possible to make as much as $72,000 as "Director." That's pretty good money, but then again I'm not sure that there is more than one Director in the entire organization. The top person responsible for an enterprrise of similar size in the private sector would certainly be making more than than, probably more than twice that amount.

The next-highest salaries, for accounting and finance specialists, are in the $62-to-65K range. A "Community Manager" ~ probably the head honcho of each local chapater ~ makes a modest $39,000, not much higher than the ACORN-wide average of $34,000.

All in all, pretty defensible, I'd say.