It's not really though, is it? Obviously those who agree are generally thinking of the Vicki Pollard types, whereas you also have people who lose jobs, lose abilities, lose loved ones, etc. If I spent my entire life feeding the system and for some reason had to stop working but then wanted another child I'd also expect the system to help out. People seem to forget that good, hard working people also suffer hardships in life which could have devastating outcomes. Why should they be denied the ability to have kids because they're not currently earning money?
It's a tough one really, but like I said, it's really not as simple as some make it out to be.