Personally, I cope fairly well with school holidays, though the additional cost is hard. I work part time during school holidays, to minimise the problems of needing to use childcare and not being able to spend the time with the children. I also have slightly longer holidays than the norm. And I have managed to persuade relatives to take my children for a holiday for a week a year, which really helps. Not everyone is as lucky as I am - eg I have a flexible employer.
But enough about my personal circumstances - I have been trying to put forward the situation of those who need to work, often full time and with only statutory minimum holiday, and sometimes as single parents, and often without having much money.
I have no problem with the government seeing schools as having a role in enabling parents to work - there is no reason why that can't be part of their, state funded, function.
I don't think that young people having to adapt to far shorter holidays when they start work is too much of an issue, though it is a shock at the time. But I do think that if there are very long holidays, this will impact on educational achievement, and that that will feed into people's future prospects, the economy etc. I don't really understand people not thinking that children go to school, at least in part, in order to become able to earn a living later on.
I hope that clarifies things - I have to go to bed now - work tomorrow despite its being half term.