I believe another reason people are okay with corruption is that it's sometimes easier to do nothing than to do something. An ordinary employee reporting fraud may risk losing his or her job, damaging relationships or even putting oneself under personal pressure; the corrupted individual might have money and contacts to protect him or her. This leaves people with the feeling that why should I become a target if nothing is going to change? Once enough people work that out, corruption slowly begins to become normal. Fighting corruption is not just about having to tell people to be honest. It's also necessary to have adequate safeguards for the whistleblowers themselves and for institutions where allegations of wrongdoing can make a difference. Otherwise, ordinary people will not take all of the risks.
It's not that people like corruption, it's that fighting it is too risky. Why would a junior staff report fraud when he knows he will be the one to lose his job, while the Oga at the top has connections to cover himself. At the end, you become the enemy to everyone in the office. That fear of "what if I report and nothing changes" is what kills many people's courage. So people just keep quiet, not because they support it, but because they want peace.
That's why just telling people "say no to corruption" is not enough. If we don't protect people who speak up, if we don't have strong institutions that actually punish corrupt people after reporting, then nobody will want to risk it. People will only speak when they know they are safe.
