The different wages for different ages annoys me as well, I worked for the Co-op who pay those 18+ the 21+ wage, so I have never been on the lower wage as I'm lazy and didn't get a job until I turned 18, but before minimum wages were set for younger people I had friends who were working for £2 an hour! I know Asda gives all staff full adult wages, I was going to get a job there a few years ago, then the wages were about £7.50 an hour as a day time worker.
I agree with you on the children thing, personally I would never be a parent unless one of us were able to be at home to care for them, whether that meant one of us working in the day, the other in the evening, or just one working, until they were at least in primary school and then I wouldn't be willing to place them with a minder/baby sitting club at school. Now, a lot of people cannot afford to live on one wage, but now a lot of people want so many luxuries, my mum didn't work when me and my sister were young, we were by no means poor, but my parents didn't waste money on cars, SKY tv, expensive clothes or very expensive holidays.
Since becoming a student I have learnt just how cheap it is to live, my rent is £311 a month for a room in a house, where my parents live you can rent an entire house for that, I pay for everything myself which is just my student loan, I could easily spend a little less too, but I love buying clothes!