We run one car between us - cheaper than the two we used to own and run. We ski every year. "Luxuries" means different things to different people though so sacrificing things you are happy to do without isn't really a sacrifice, is it? There's a thread elsewhere on the forum with people discussing their favourite aftershaves, and some people are talking about stuff that comes in at £100+ a bottle - I wouldn't spend money on that, for instance. Some people smoke, and I don't. There are too many examples to list. And what we are doing is investing in our child's future - if that's a sacrifice, then it's a bloody good one in my book.
We live within our means, run a car, go skiing most years, buy a house and save up towards private education. It's not "proving a point", it's making a choice and budgeting accordingly. The only advantage we have that others might not have is that Mrs Tree gets a discount on the school fees due to her working at the school. Even so, pre-prep fees are lower than prep or senior fees and within reach for any couple on £50k a year gross IF they wait a few years before having the first child.
The sacrifice we are making, if any, is that we have chosen to wait a couple of years before having our first child. As I said before, she only left uni five years ago and is 26 years old, so even this waiting does not feel like a sacrifice. If she had started having children the moment she graduated then she would have been satistically less likely to have even gone into employment.