There are times when people just have short attention spans. Sure, I'd like to sit down in a chemistry discussion about how Chaindrite Foam works effectively. However, commercials are most likely meant to carry some form of hyperbole--such as making mozzarella stretchier than it truly is or doing some crazy stunts with a disclaimer. This Thai insecticide commercial gets really funny.
What I love about these commercials is the cartoony effect. I assume the foam used in the commercial is either shaving cream or whipped cream. It's because spraying the actors with the actual foam playing the giant pests would be dangerous. The actors playing the pests are made to dress up like mascots for a school presentation. Seeing the actors play the pests dying is rather entertaining.
I believe that the purpose of giant pests isn't just for laughs. It's also to address that the problem can be that huge. Pest problems can cause so much trouble. It may be a good attempt to raise awareness of how pests aren't a laughing matter--while making the audience laugh. The giant pests' deaths in these commercials can be funny. After all, who wouldn't be satisfied to see the pests die? It can be disturbing but also satisfying at the same time.
These are probably creative ways to sell a product. It would be good to tickle the senses without otherwise exaggerating the claims.