Perhaps these people are putting their beverages in the wrong end? Coffee and juice goes in the mouth.
The only bad things I can say about centrifugal juicers are that they can't juice everything (such as wheatgrass or brocolli) and they leave a small percentage of juice in the pulp (who cares?). I plan to buy some other types of juicers in the future, especially since I have a vineyard and have found that our Cabernet grapes when juiced are like nectar from heaven, much better that fermenting it into a boutique wine and much better for you.
If any of you can find a vineyard that will sell you a bucket of cabernet grapes to press, don't hesitate when they are in season. It's unbelievable. You may even get a deal on the ones that have gone a little past season as the wine makers don't want too much Sugar whereas for juice it's just fine.