Scope of exaggeration
Advertising is about being loud in telling your story. More often than not some ads tend to go overboard with exaggeration which might look lame and not go well with the audience. When it comes to animation, you can do that in a jovial way that people would take sportively. It is the ‘suspension of disbelief’ while watching a cartoon that makes it fine for animated videos to go slightly full retard.
Making Live action videos is expensive. Scouting for locations, actors, high end cameras, lighting and sound equipment and what not? And if you want to show Eiffel tower in your video, well it is a different ball-game all together. Sitting in front of a computer, animation makes it all possible at a much lower cost, in a slightly different and fun way.