About Sincerity

I was conveying to kenric that we hadn't really been very honest in playing the game fair. We fouled the players clandestinely. Kenric said: We did it when the referee wasn't looking.
I told him: Why do it at all? If we can win, we should be able to win without fouling else it just means we couldn't do without fouling and thus we are not really the best team. I further added that We have to be sincere even if the referee isn't watching. Kenric said: It was just a simple football match not an international match. I asked him if that makes a difference. Let us be sincere in everyday ordinary activities no matter how commonplace they are. God is watching all of these and not only international matches. And if you do have to be sincere, then be sincere all the time. why choose when to be sincere and otherwise? The goodness of the sincerity is in the choice to be sincere and not how much fruit the actions of sincerity will bear (say in an international game, it may bear much fruit to be sincere)