Maybe you were sarcastic in which case you should ignore my reply (which I should – but you don’t have the right to – delete subsequently).
Hey kitty, Never Wrestle with a Pig. You Both Get Dirty and the Pig Likes It.
To be clear: I’m the pig in this setup, actually even a bore boar as I learned yesterday. 
Oooh, did I say that? Naughty Goofy! Slap on the wrist.
Let me break it down for you:
Someone earning CHF 4k a month
This meant to suggest that the person lives in Switzerland and earns CHF 4k a month, so around CHF 3.3k to 3.5k (tax, social security deductions, etc) netto …
shouldn’t
It’s a linguistic detail, I understand, lots of nuance to be explored for the uninitiated, but …
"shouldn’t* ≠ “don’t have the right to”
own a car
Owning a car that’s roadworthy in Switzerland costs you (just to buy) maybe about half that monthly salary of CHF 4k?
You have every right to do this, but if your monthly salary is CHF 4k, and you support your family on that low budget, taking them on holiday to Italy in your car that costs you ½ francs per kilometer and wanting to spend CHF 60 extra (because of that potential increase in the vignette): it’s a choice that you make.
Not saying it’s right or wrong. Just saying passing judgement on if CHF 60 is an issue for you, maybe you should not own a car which comes with somewhat fixed costs of probably at least CHF 100 per month if you own it in Switzerland and do not even drive it one kilometer.
?
This was meant to indicate that it’s a suggestion to think about this choice.
We’re slighty off topic … or are we?