Nonsense. You don't need that much data space. For me 8 Gb would last a life time!
Tell me. What happens when you use up all that data and something happens to it like it gets stolen or run over by a bus? What a waste. That's the problem with these mobile devices. People put all their information on them without backing it all up. Why can't you just use computers like a normal person?
People have tens of gigabytes of music they want to take with them. Indeed the tablet is acting as a backup device for this purpose as well, instead of all the data being beholden to a single computer.
Other people want to watch TV shows, movies, etc, on the move. I see this frequently when commuting. These files are not small. And if purchased online, they're re-downloadable if you do lose them.
Then there are large apps (especially games).
8GB on a tablet would leave you gasping for storage before you had even started.