The ad companies have to deliver the same impact in a shorter amount of time. This leads to catchier graphics, more quick-cuts, and more associative, intuitive messages. Whether this leads to smarter citizens is a different matter. I know I was both intruiged and disturbed by the quickness and jumpiness of European commercials. On a side note, us Americans observed the Irish had the uncanny ability to talk to each other all at the same time and call this a conversation rather than a cacophony of interruptions and cross-talk.
Phone companies are clever, annoying, and immoral.
Advertising is a necessity. It pays for everything. Every medium you can think of would be nonexistent without it. Radio, TV, Film, Devil Shat, everything. I too don't like seeing advertisements before films, and before I left America seven years ago, I was never subjected to them in US cinemas.