...rick, they're not goobers and they do help at times...do you think they should do away with coaches?...of course not.
...their salary is really irrelevant because again, they simply don't make that much when compared to managers and players. Plain and simple, they are there to offer advice and assistance if/when a player needs it...just as with pitching coaches, they go over film together and try to spot something that will help them improve...they take that info to the batting cage and practice it...but when the games starts it's ultimately up to the hitter to apply it.
...I say it again, hitting coaches alone don't turn a poor or mediocre hitter into a very good one...and hitting coaches don't turn good.great hitters into bad ones because if a hitter is in a groove you don't try to fix something that is not broken.