Lily, it may have little to do with average places, average standards, averages, or even clients vs agencies or specialists vs theorists, just A company needs two specialists, so two job applicants come to the interview. When asked about a desired annual salary, the shy seeker babbles that some $25,000 would do for the entry position. OK. The other confidently replies that it should be at least $75,000 a year net with benefits. And it’s also accepted, why?
On the whole, I agree that some $0.001/word flat (counting the 'discounts') is less than a fresh undereducated McDonald's guy gets per hour. On the other hand, if a no businessperson cannot justify the rates and negotiate more favorable terms or has no 'red line' (absolute bottom), then it's still just a part of the lesson.
Ask for more than you expect to get--you may just get it!