Yes I agree, it's a little bit unreasonable if they obviously can't cope and they can't afford childcare. I suppose it's personal choice, and every life is sacred.. There are other considerations to having lots of kids though: moral, environmental to name just a few.
I made a decision to have one biological child, and never wanted another - we have low infant mortality now, so I don't need to have six in order that my genes are passed on by at least one survivor, and I live in a city, so I don't need many hands to make light work down on the farm. Also children are an environmental disaster - (as are pets by the way, unless, that is, you keep rabbits, and they are carbon neutral, BUT only if you eat them!!!).
The ecological footprint was a factor in my decision to have only one biological kid. I care about the planet, and what kind of planet we will all be sharing with 9 billion humans in 2050. We reached 7 billion people this year, and the planet looks like it's going to hell in a hand basket - climate change and habitat destruction to name a few concerns, all fuelled by people's need to eat and have space for themselves. I don't keep a car any more for environmental reasons: I use public transport, walk or cycle, and I don't have a pet.
Sometimes I look at large families and I just can't see how someone who claims they are educated would choose to have so many biological kids. It's just so greedy and irresponsible: there's a huge double standard too globally as we fund charidees to help the 'poor' Bangladeshi woman, and implicitly berate her for having too many kids, or the Nigerian woman, weighted down with babies, but with no land tsk tsk, but there we are driving our 7 seater SUV, with the family dog too - just wolfing down the global resources, and polluting like there's no tomorrow.
For me it's a no brainer not to add to a problem if I can help it - and contraception is a way to help the huge over population problem the whole earth has! Contraception is not just for 'poor' people with dark skin colour, living in low coastal regions or near the equator, it's for everyone, even those living in middle class ghettos in the northern hemisphere.
I don't think having just one child makes you any less of being a parent than if you have a football team - if you're woken in the night, you're still awake, not half awake or a sixth awake. Having one child makes you a parent.
I know it's personal choice to have as many children as you like, but in my personal opinion having more than one child in this day and age, when we are mostly urban, when childhood mortality is rare, and living in this already environmentally fragile planet, is just plain old greedy, and environmentally not a little shortsighted. You don't have to collect the full set you know!!
It's not rocket science to figure out how to be more responsible, think globally and act in the best interests of every creature on this planet, and that includes using contraception. If you need to have more than one child, there are plenty in care and orphanages who might like to be adopted or fostered by you.