A recent newspaper advertisement for Ryanair has a big picture of Robert Mugabe shaking his fist, under the headline: "Here's EasyJet's New Head of Punctuality". This sends out a confused message. I'm no Zimbabwe expert but I'm fairly confident that the main charge levelled against Mugabe isn't one of unpunctuality. It's no more meaningful an insinuation than saying that Kim Jong-il is Virgin Atlantic's new head of catering or that Mel Gibson has been taken on by Thomas Cook to handle its IT.

And while Mugabe's an evil man, there's no reason to think that, had history panned out differently, he mightn't have made quite an effective "head of punctuality" for an airline. If what people say about Mussolini and trains is to be believed, a bit of murderous megalomania doesn't go amiss when it comes to getting transport services to pull their socks up.

But we'll never know how he'd have got on because Robert Mugabe isn't easyJet's new head of punctuality at all. It's not clear whether he even applied. Apparently he really, really wants to stay on as president of Zimbabwe. It would have been an eccentric career change – like when Alastair Campbell moved from handling the press for that unsuccessful war to doing the same for a rugby tour that went even worse. But maybe, like Campbell, Mugabe would have been glad of the comparative rest. EasyJet, for all its faults, isn't as unpopular as the government of Zimbabwe. It's not like it's Ryanair or something.

Ryanair is the unashamed villain of the corporate world. Other companies probably do worse things but Ryanair is the only one that delights in stepping into the public eye wearing an opera cloak and laughing maniacally. This horrendously unfair advert is typical. The sole basis for associating its rival with a brutal kleptocrat is a couple of quotations from newspapers both quoting the same third source claiming that easyJet's flights from Gatwick are "less punctual than Air Zimbabwe".

Michael O'Leary and Ryanair realise that this will seem underhand but they also know that their customers don't need to like them. They're running a "no frills" airline and have worked out that frequent flyers subconsciously consider civility and fairness to be frills. "These people will keep their prices low," we secretly think, "even if they have to treat us like cattle and stab their competitors in the back to do so."

This approach is unusual and refreshing. Most companies persist in trying to persuade us that they're nice and care about charitable causes, the obesity epidemic, equipment for schools or the environment. As I've said before, they're incapable of caring – they're merely trying to make money for their shareholders and believe that this affectation of human feelings will help them to do so. Conversely, Ryanair has attracted customers canny enough to know that a public company can only have mercenary motives but who are happy to do business with it anyway.

BP has not reached this level of corporate development. In common with most other oil companies, it spends a lot of its marketing budget assuring us that it's obsessed with alternative forms of energy – that walking on to a BP forecourt and asking for petrol is like trying to buy a VHS cassette at the Apple store. "Petrol, you say? Not much call for that these days. Wouldn't you rather a quick zap from a solar panel or wind turbine?"

This strategy led the Today programme's John Humphrys to ask a silly question last week: "Isn't the reality that so long as the oil companies are as greedy for profits and nothing else as they are, this problem is not going to go away?" he said, with reference to the issue of replacing oil with renewable energy. It's silly because it only demonstrates Cynicism 1.0: he knows these corporations aren't as eco-committed as they claim because they can still make money out of oil. But he implies that a time might come when plcs aren't "greedy for profits and nothing else". Cynicism 2.0 is realising that it won't and that we can only properly harness the power and wealth of oil companies for developing sustainable energy sources by creating a business environment in which that activity is as profitable, or looks like it will become as profitable, as drilling for oil.

The continued prevalence of Cynicism 1.0 is presumably one reason BP considered it politic to remove its chief executive, Tony Hayward, last week. The oil spill is an environmental disaster and the company still thinks it's worth trying to appear as if it genuinely cares about that, and not just about the consequent financial and reputational cost. So heads must be seen to roll, even if Hayward's was detached by a generous severance.

The generosity is because no one at BP, and few unemotional external observers, holds him particularly responsible for the disaster. At worst, he's deeply complicit in a corporate culture where such spills weren't made as unlikely as they could have been – but that's a long way short of it being directly his fault. At best, it was a very unfortunate accident and he's blameless. He made some PR gaffes and seemed a bit callous, but no one has suggested that any of that either hurt or saved a single extra sea bird.

This makes the decision to axe him seem illogical. Businessmen of his seniority are incredibly well paid and this gets justified by the claim that their acumen is so rare that they more than earn their wage. If this is true, surely BP can ill afford to lose a man who has ably run the firm since taking up his post in 2007 merely because his tenure coincided with an accident? If he was worth the money they were paying him, he will not be easily replaced.

Yet he has been, and things will be fine, says BP. Apparently it wasn't like trying to find another Andrew Flintoff or Tom Stoppard – people with amazing talents in their fields. It was more like replacing a good heart surgeon: Hayward's skills are uncommon, but not unique. He isn't, for example, the person who finds all the oil. That such executives know they're over-remunerated is implicit in their "it was nice while it lasted" willingness to step aside when their luck, rather than their competence, runs out. Deep down they know they're only human.

But I doubt Michael O'Leary would go that quietly. Neither, for that matter, has Robert Mugabe.