There are some genres of newspaper story that never die. Among them are sightings of Lord Lucan, public moralists discovered in adultery – and foolish MPs being caught out offering themselves for hire to undercover hacks. A fine example of the third of these broke yesterday thanks to the situationist campaigning group Led By Donkeys, who started out as Brexit-bashers but have expanded their remit to the broad-brush embarrassment of MPs. You’d think, by now, that senior MPs would be a bit more on the qui vive for this sort of thing. But no: they never learn. This sort of sting is now as much of a British tradition as ambushing cabinet ministers on live TV by asking them how much a pint of milk costs; and like that stunt, it works nearly every time.

It’s easy-peasy. You pretend to be a foreign company with a mahoosive budget, approach an MP to be a non-exec or a consultant and then film their sweaty little faces and dollar-sign eyeballs in the job interview before putting it online for the amusement of the rest of us. Everyone likes money, and most people go a bit stupid when there’s the prospect of earning lots of it for doing sod all, so if you approach a couple of dozen MPs with this dodge you’re generally off to the races.

So it has proved again. This time the fall guys were Graham Brady, Kwasi Kwarteng and Matt Hancock. (Stephen Hammond, apparently, walked halfway up the aisle before smelling a rat, but no matter: most of us have forgotten who he is anyway.) I dare say they will all now be mortified. Whichever way you slice it, £10k a day for a side-hustle looks a bit toppy, especially when – as there will be no shortage of people to point out – your party is resisting letting nurses and teachers earn a fraction of that for their main jobs.

Focusing rage and ridicule on Brady, Kwarteng and Hancock is easy to do, and it is fun. But there’s no hypocrisy

Anyone who expects to earn the national annual median wage in three days flat tends, like it or not, to forfeit much claim on public sympathy. It feels a bit of a thankless task, then, to defend them. But here goes. They did, as far as we know, nothing wrong. If the parliamentary rules allow sitting MPs to take second jobs, and sitting MPs are offered second jobs, we cannot be surprised when they show an interest in taking them. Nor can we be surprised if they take the unexceptionable view that, when some foreigner with more money than sense is fool enough to offer you megabucks, you might as well fill your boots.

Focusing rage and ridicule on Brady, Kwarteng and Hancock is easy to do, and it is fun. But there’s no hypocrisy. All these men are professed free-market capitalists. I don’t believe any of them have spoken against the practice of MPs having second jobs. And all of them, according to reports of these meetings, made clear that they were not prepared to lobby or peddle influence improperly. The size of the paycheck is, on the face of it, irrelevant to the propriety or otherwise of the job. It’s just headline-bait. It dodges what the late Tony Benn would have called the ishoos.

A complete moratorium on side-hustles for politicians would deprive us, among other things, of Jesse Norman’s fine biographies of Adam Smith and Edmund Burke, Nadine Dorries’s popular fiction and many an amusing turn on Have I Got News For You? I can’t see why – provided they fulfil their parliamentary duties to the satisfaction of their constituents – it serves public life to say MPs can’t earn any sort of money in any other way whatsoever. Besides, there’s a decent case that if you did make such a rule, you’d discourage some talented people from entering politics.

But there are side-hustles and side-hustles. Isn’t it possible to make a distinction between jobs you might do despite being an MP and jobs you are asked to do because you are an MP? Our imaginary Koreans, who claimed to be looking for advice on how to ‘navigate the shifting political, regulatory and legislative frameworks’ of the UK, certainly seem to fall into the latter category. Brady, quite properly, told the undercover pranksters that he was bound by strict ethical rules against lobbying. He explained that his help would perforce be restricted to identifying the best people to approach in government and advising on the ‘most appropriate way to approach them’.

I’ve no reason to suppose that Brady had the faintest intention of doing anything improper. But the suspicion will arise that he might not have minded his prospective employers imagining that they would be buying more influence than they were. Few companies would cheerfully fork out tens of thousands of pounds for a couple of email addresses and some advice on the difference between ‘yours faithfully’ and ‘yours sincerely’. If that sort of milquetoast guidance really is worth ten thou a day – and if government is opaque enough that only companies with very deep pockets will ever know how to make themselves properly heard within the rules – that’s a problem for our democracy. Isn’t it?

It seems to me that to avoid the further egging of noble faces by this sort of sting operation either the rules, or the culture – or ideally both – need to change. Just over half the public, according to polling data, disapproves of MPs having second jobs at all. If MPs don’t want a slender majority to turn to unanimity, they might think about working on a culture where not only is influence-peddling ruled out, but the appearance of influence-peddling is ruled out, too. And they might want to be wary of Koreans bearing gifts.

Funnily enough, I have first-hand experience of Kwarteng’s willingness to take on outside employment. He has contributed a fine book review to the next issue of The Spectator. I’m glad to have it and I’m glad no parliamentary protocol prevented him from writing it. Its theme? The relationship between capitalism and democracy.