I am on the board of a credit union. Credit unions must make a profit or they will die. They must have some fee structure to offset costs of members who are expensive to service. The idea is that fees should be minimized to the extent that the CU can run a healthy business in accordance with its mission.
Since it is a non-profit, the board is unpaid. We are members who volunteer our time. We must make decisions in the interest of the membership as a whole and that means working with the executive staff on decisions related to which services we can provide to the members and how those services will be paid for.
The distinguishing difference between a credit union and a bank is that banks can raise capital in the open markets by issuing shares, issuing debt, or taking on risky bets in the form of loans and investments.
Credit unions, on the other hand, can maintain capital only through profits from loans, investments, and certain income like fees and interchange fees. The investment side is tightly controlled. Investments are boring - bonds, CDs, money markets. The best income is from loans.
There are good credit unions and bad ones. When the bad ones go under, the credit unions are collectively assessed via the NCUSIF (in most cases) to make the the depositors whole. Or the NCUA works with the failing credit union to merge them into a healthier one. But we are all collectively responsible for each other in a small way -- yet we compete against each other and banks too.
Even though I've been with the same credit union for 22 years (and now on the BOD for 3 so far), I don't label "credit unions = good, banks = bad." I also have an account with ING Direct and had excellent customer service - all by phone, mail and email - for a mortgage a few years ago.
Do your homework and figure out what you need and talk to people you trust. Don't think that you are necessarily constrained by a credit union. You might not be. It depends.