It still is appropriate because it's compensation for a job. VA benefits are part of the package deal a service member signs up for. Without those benefits the military would have to offer a higher salary to recruit the same number and quality of employees, at the margin at least.
It's like saying a government pension shouldn't be counted as part of the cost of employing government workers because the workers would still have to buy food and housing whether or not their career was with the government.
By that logic you could affect the spending numbers by charging military spouses rent and making up for it with daycare pay to compensate them for watching their kids. It's just a difference in accounting.
I'm confused about what you're arguing. If governmental funds are being spent on military spousal housing, that's a cost of the military, whether it's accounted as salary to the service member who pays rent or if the military builds the house directly.
My original point is that nobody (at least publicly) knows the true spending on the US military because the accounting is so baroque. The VA is just one agency whose rather significant cost is typically forgotten when quoting these numbers, but it's far from the only example.
That might have been a bad example. But if you're comparing military spending between one country with the VA and another with universal health coverage, it will mess with the numbers if you include the VA. It's the other country with the difficult accounting.
But I don't want to compare countries. I'm not sure if there's a "right" level of military spending, but I think pro-Military-Industrial-Complex forces in the US purposefully obscure the cost in order to not erode popular support.
It's like saying a government pension shouldn't be counted as part of the cost of employing government workers because the workers would still have to buy food and housing whether or not their career was with the government.