How is it a waste? It's a game many have been waiting for 3+ years now.
Same with Smash Bros. for Wii U, but they didn't use E3 just to talk about it. They gave it it's little direct, focused a little bit of it in E3 and then placed focus on everything else they have. Nintendo could have used E3 to focus more on:
Shin Megami Tensei IV: Apocalypse
Dragon Quest Games
Pokemon Sun & Moon
Phoenix Wright: Ace Attorney - Spirit of Justice
Metroid Prime: Federation Force
Monster Hunter Generations
Paper Mario: Color Splash
Or anything else they have cooking right now, but no, just Zelda. It's great for Zelda fans but for everyone else it's gonna be a complete bore.
You, watching online, will only see 1 day of streaming. But people attending will have 3 days to play the game extensively.
I'm not complaining about the floor stuff, I'm talking about in terms of a presentation. They are just going to get lost between everything else going at E3 at the time. Microsoft & Sony will have multiple games to show off while Nintendo will only have 1. That's like Microsoft focusing it's whole event on Halo and Sony focusing it's whole event on Uncharted.