Yes, it's true. When you juice, you have a LOT of leftover pulp, the bulk of the fruit and veg that wasn't juice. If you become an avid juicer you realize that you throw away a lot of pulp. And while it's true that it doesn't have hardly any vitamins or minerals left in it, it is still great for fiber! Wonderful fiber! And did you know that there are actually several fantastic uses for it? Keep reading and I'll tell you what they are.
You can add that lovely pulp to practically anything. Well, for one thing, if you like pulp in your juice you could just plop a little back into your juice. Not too much though, otherwise you'll be drinking your juice with a spoon. (Yeah, we discovered that one the hard way.) You can also add it to any baked good. I've added it to bread, cakes, pancakes/waffles, and all kinds of cookies. You can also add it to soups, dips/spreads, smoothies, lasagna, pasta sauce. The list is endless really. You will have to adjust your recipe slightly to accommodate for the extra moisture, but it can be done.
Now I will say that not every kind of pulp tastes great in everything. You do have to kind of use your head here. I took the pulp left over from one of my veggie packed juices and added it to a bread similar to a banana bread, and while it didn't take bad per se, it didn't taste good either. So be prepared for a few flops. But I've learned that carrot and apple blends tend to go well with most everything.
Here are a few websites with great ideas and recipes of what to do with all that left over pulp:
All About Juicing: Ideas of how to use it
All About Juicing: Recipes
The Kitchen: Recipes and ideas
Those are some great places to start. As with anything, experiment! Be adventurous and try new things! You might even surprise yourself.