A glance through the latest questions on notice in the Senate is revealing. The Labor opposition wants every detail of public service spending on, for example, "non-conventional therapies" for staff, "office plants", "office recreational facilities", "wine coolers/fridges" and "coffee machines". It also seeks other, less frivolous information, such as the sums spent on advertising campaigns and market research. But, on the whole, it is hard to escape the impression that much of the opposition's work revolves around an elaborate game of "gotcha!", designed to score a quick political point against whichever minister was responsible for the allegedly "wasteful" spending.

Neither the Coalition nor Labor stands on the moral high ground: both play out this same ritual when they are not in office. Parliamentarians on all sides know that ministers are never involved in low-level spending decisions within their departments. But none of this matters in the games of Parliament: the minister is always, somehow, to blame.

The problem with this tit for tat is that, in many cases, it assumes that any efforts to make government workplaces more attractive for staff are innately wrong; that buying, for example, plants to brighten an office is an offence against taxpayers. When Liberal frontbencher Jamie Briggs was in opposition, he chided the bureaucracy's purchase of high-quality espresso machines, saying: "From overpriced school halls to gold-plated coffee machines, Labor's wasteful spending knows no bounds." Last week, it was Labor MP Pat Conroy's turn to play the hypocrite. He attacked an agency that spent a tiny sum subsidising a yoga course (staff paid 80 per cent of the costs), saying: "It's just a joke. I know the government has shown an ability to hold multiple positions on policy, but yoga training is taking it a bit far." Mr Conroy also criticised management training for public servants, even though the same courses were provided under the Gillard government.

Public servants should expect every aspect of their spending to be scrutinised, even trivial expenses; it is a price of public life, of which bureaucrats, not only politicians, are a part. Indeed, public servants could neutralise these time-wasting games of oppositions by being more forthright: if much of the information that is eked out via Senate estimates and freedom of information law was published routinely online, the "gotcha" element would fade from public debate. The FOI Act actually obliges government agencies to do this; it requires them to set up an "information publication scheme" under which they are meant to "proactively" publish the kind of documents and data that parliamentarians often seek. However, few agencies bother to use these schemes to publish anything more than a handful of corporate reports.

Nonetheless, departments should not apologise for caring for their staff's well-being. Many studies show that happier workforces are more productive. Like any other employer, the public service must battle to retain skilled workers. Government policies sometimes prevent the bureaucracy from paying high wages, so other benefits can be crucial in luring staff. (It's worth noting that a company such as Google, which receives awards for treating its workers well, would never subsidise yoga classes for employees – it would pay the full cost.)

Lost in these debates is another, important point. For all the arguments around public service spending, the sums involved are relatively trifling. The Abbott and Gillard governments both targeted the bureaucracy by increasing the so-called "efficiency dividend", an annual cut to operating budgets that the Coalition's national commission of audit labelled a "particularly 'blunt instrument' ". The entire dividend, 2.5 per cent of total government running costs, "saves" about $2.5 billion a year, causing immense upheaval and thousands of redundancies in the processes. But, to put that amount in perspective, last month's mid-year budget review showed that the deficit for 2014-15 had, in just half a year, blown out by an extra $10 billion. Why? Because of fluctuations in income tax revenue and Australia's terms of trade. That's right: nothing to do with public servants buying too many coffee machines, nor any other efforts to cut spending.

Perhaps one day our parliamentarians will realise that "gotcha" games, no matter how many points they win, will never produce a surplus.