For the first few years of my career after college which has a pretty generous 401k company matching scheme I put the maximum amount possible into my retirement accounts and lived well within my means to build up a nest egg. Now that I am married I have dialed back my investments so we can afford to live a little bit nicer with the knowledge that we have a really great start in our retirement accounts.
My wife and I moved in together two years before getting married. This made living substantially cheaper for both of us and made us positive that we wanted to live together and could tolerate each other prior to tying the knot :).
I got a vasectomy mid-last year. My wife and I both agreed long before marriage that we only want to adopt. Adoption is obviously very expensive, but now we have the peace of mind of knowing we have full control over when we start to invest in that process to expand our family. No "accidents" can happen which is very liberating.
I have a similar story as your first point. It boils down to tucking away money with each financial gain. I put in enough to my 401k to get the full match, then with each raise, increase the amount invested by the raise. I'd already learned to spend within my limits and had no credit card debt, so each raise was "new money". Years later, after adjusting our financials to pay for daycare, when the daycare expenses dropped (infants are most expensive, costs drop down as they age), we started putting into a college savings and some for school expenses. We had saved up enough to pay for private school, which was less than daycare. Now that private school is done, college is paid for, we're paying down the mortgages. We locked in at 3% years ago. The house will be paid off when the kid graduates HS and we turn 55 and are eligible for the employer's retirement program, including health care. We plan to travel in those years where we're young enough to be healthy and old enough to have some money tucked away.
Oh, we also did the same for cars. When the car was paid off, we'd put the same money into a separate bank account and when it was tome to look for a new car, we had almost enough to pay for it outright.
Of course all of this can only happen when you have the skill to spend with your means.