I Am Legend - Alternate Ending

I'm here again. It happened many events before I wrote again and from my point of view, that's one of the most amazing things.
Here, you can watch an alternate ending of the film I Am Legend, starred by Will Smith. That's the real ending which is written in the thriller. But, the person responsible for marketing said that's ending didn't sell so much as the other one ( the ending showed on the film ).
Whoever wants to watch it, look for it on YouTube or watch this one I put in.