This is showing in the UK at the moment, we have a lot of advertising from banks and supermarkets with athletes because of the past Olympics.
I know at the end of a day it's selling a product, but it's also getting across to kids that the Olympics is cool. And generating big money equals funding!
For bolt and the others who have been placed in ads it is great. It is good for the whole sport. Usain Bolt has monetarily been the most successful Track & Field athlete of all time. He makes around $18 Million / year which is great. He is the fastest man to ever walk the planet and it will be hard for anyone to break his records for a long time. Unfortunately there is a very sharp drop off in pay for others .