"Honesty is the best policy"

Yesterday i saw the movie GURU,starring Abishek Bachan and Ishwarya,directed by Maniratnam,Ravi.K.Chandran visualised the movie.Kalaignar T.V broadcasted the movie.

The story of the movie was about a business man, who started his business with low finance and high hopes.He struggled a lot to find his place in the market.He established and improved his business and brought it to top gear.at last,he had created a business dynasty under his rule.
He did many business tricks,travelled on road against our indian law to create the dynasty.finally he succeeded in everything,he overcame all his problems with his competitors and with the govt.
Let's come to the point.gossip regarding the movie is,the story reflects the life Dhirubai Ambani.big giant of indian business industry who owned Vimal industries and
Reliance industries.
If the story really reflects Ambani,then what is the point of honesty.today Ambani brothers are doing well and every year they occupied good position in world richest people list.
Eventhough they're doing well in business,they're corrupting almost all the sections in govt.

Please clarify my doubts.

Why do we follow rules and regulations?
Why do we believe the proverb "Honesty is the best policy"
Why our indian govt.creating laws,rules and regulations?

In our country,whether the rule is for an ordinary people or common to all.