Advertisers pay premium price to have the chance to advertise their product during the Olympics.
Senior lecturer in marketing and University of Auckland Dr Bodo Lang says the size of the audience and the buzz around the events attracts the big spending advertisers - the global companies.
"The Olympics has huge pulling power in terms of audience. People get really excited about the Olympics because we don't have them very often and they don't go on for very long," Lang said.
"The content is highly anticipated, so it's pretty desirable for advertisers."
The cost of an advertising slot during the games would be high, Lang said, so the television commercials will generally be taken out by those big corporations.
Fonterra, ANZ, Powerade and Visa have highly visible ads screening during the Rio games.
The Games "embraced the human spirit" in a different way than other sport, Lang said.
"Other content can often be very limited in terms of the demographic reach but the Olympics has a broad appeal across a vast array of age groups, gender and ethnicity.
"The Olympics is about passion, drama, it's highly emotional content... and that lends itself to ads that have a similar appeal."
ANZ is a major sponsor of the NZ Olympics team - a deal which would involve a massive amount of money, Lang said.
"They're working really hard to position themselves as a New Zealand brand, and this is the perfect place to do it because the Olympics are about national pride."
Five of the best ads of the Olympics
Anchor: Start Strong Go Strong
The ad features pole vaulter Eliza McCartney starting her training days with a smoothie made with Anchor yoghurt.
ANZ: Dream Big Olympics app
Using the same "Dream Big" poem from the Cricket World Cup, ANZ advertises its official Olympics app by showing our athletes looking at the stars above Rio and seeing messages sent from Kiwis back home.
Powerade: The Power of Blue Bloods
The ad shows athletes preparing to compete as knights mount their horses ready for battle.
High Performance NZ: Hamish Bond
The emotive ad shows up close the hard work Bond puts in and that "greatness lies in the smallest of margins".
Visa: Carpool to Rio
The ad was screened in the build up to Rio and generated plenty of enthusiasm from Kiwi fans to see Val Adams lead Olympians from all over the world on "the road to Rio".