Setting fire to your house to make use of the fire service your taxes fund is the wrong analogy.
Here's a more accurate one:
Imagine that you had installed a smoke-activated, fire-preventing sprinkler system in your house - bought at your own expense, out of taxed income. As well as paying taxes to fund the fire service (which you're fine with).
And that worldwide nobody puts VAT on sprinkler systems, because sprinklers reduce fires, which is good for everyone.
But now some people have decided that you should pay VAT on the sprinkler system.
You point out that you're reducing the load on the fire service (which you still pay for, exactly the same as everyone else), and that putting VAT on sprinklers means that some people now won't be able to afford them - which will mean the fire-fighters (who are already stretched) will have to put out more fires. Those fires will cost the UK more that the VAT on sprinklers will raise. Nobody worldwide puts VAT on sprinklers, for exactly that reason.
Is that selfish? Or is that just pointing out the fucking obvious, with the intention of preventing a completely stupid policy?
But then people get cross and say "we don't care if this means the fire fighters will be less available to put out fires in our own houses. It's unfair that you don't suffer fires (because of the sprinklers you paid for). We'd rather our houses burnt down more often - because the fire fighters are now too busy - so long as you get the same number of fires as us. "
It would surely be unreasonable to expect you to be OK with that. You'd more likely say 'Well fuck you, you bloody idiots'. Even more so if that spiteful stupidity is aimed at your children.
And then someone might point out that some people have sprinklers because they're disabled, and so it's harder for them to get out of a burning house. You're not in that situation yourself, but can empathise with it.
But the same nasty, spiteful people say they don't care. That if the person is so disabled that they can't get out of the burning house at all, then the government should pay for the sprinkler system (when in reality we all know that the government fights that with everything they've got, for years) and everyone else should just struggle their way out, even though it's much harder for them.
Who exactly are the selfish ones here? I don't think it's the people with sprinklers.