Depending on the state of what we rather inaccurately call our 'economy', there will typically be a number of people earning, and paying taxes, and other people who are not earning, or earning less, and are receiving benefits.
This is one of those great sources of resentment, and a bit of a political hot potato. Those that are working and giving up some of their income in taxes, do so begrudgingly and usually with the complaint that it is too much. Those taxes get justified on the grounds of social welfare, compassion and ultimately, need.
If we consider unemployment, our welfare system aims, to a greater or lesser degree, to cover for the needs of the unemployed person and their dependents - needs such as: food; clothing; shelter and assistance in finding new work such as travel and training.
As Mr Angry Taxpayer, I'd want to ensure that my money is not being wasted - that my money is being spent on needs, and not on luxuries and excesses.
"No!", I hear the protesters shout, "You can't control how someone spends their money. They are free, not criminals" (criminals, ooh... there's another topic for another day).
Well let's look at this. Can I as a tax payer dictate that someone cannot buy, say beer, or cigarettes, if they are unemployed, and receiving benefits? Of course not. Our liberal society protects people's freedom of choice. They can do as they please within the law. They can spend their money how they please.
But wait! Their money? Who's money is it? The conventional story would be that originally, it's mine, the tax payer, and then, it's the government's, and then it belongs to our unemployed beneficiary.
Another way of looking at it is that it is never the government's (it remains the property of the tax-payer and they are being entrusted with using it for the purpose for which it was taken), and arguably, they should ensure that it is used for the prescribed purpose and nothing else.