I didn't make any comment about whether what CPAs charge is reasonable or fair.
My point is that for many people, doing taxes is not too complicated & why pay someone else to do something you can do yourself (especially if you're paying that someone else more than it would cost you to do it, based on what you currently earn per hour after all taxes (income & payroll) are paid). Even if it does cost you a little in terms of the value of your own time, you also need to factor in other value that it gives you.
There are advantages in doing one's own taxes in that (1) you improve your skill in reading IRS pubs & thus, ability to understand tax rules and (2) this knowledge helps you better understand the tax implications of decisions (and to figure out what the tax implications are).
I tend to do quite a bit that others hire someone to do. Sometimes it takes some time, but even if I hire someone, I'm usually going to do research to education myself & to verify what they're telling me. For most home maintenance, I trust myself (including my ability to learn & do quality research & ask questions) more than most people who are are in the business of charging others (yes, there are some who are very competent, but I have to weigh whether I can afford to pay a premium for those people or whether I should do it myself). One exception (for the most part) is my mechanic - I trust the garage & quite honestly, feel they undercharge me (& have told them that!).