"I think your twenties are for experimenting and finding out what you want to do with your life."
I agree with the above statement and I'd add in having fun, while you aren't fully mature.
Yes, you can take holidays later but you've changed, so your holidays will.
I'd had my first child in my 20's, i had secondary infertility, so that dominated my 20's as well. I was Widowed in my 30's, with three children. All our future holiday plans obviously didn't happen. Neither did our house plans. We were fucked over, as many people were by our endowment mortgage, coupled with terminal illness, we had to sell.
However, I'm now mortgage free again and can travel. But, It's all a bit samey-samey and alcohol is no longer my friend, i also can't eat what i want, as most post Menopausal women can't. But if you do, then your energy levels are rubbish. That changes a holiday.
@Ohtheroses, surely in your peer group ypu know of many people who started to have health issues from mid 50's, but increasing by their mid 60's? You can't predict that you can still do the type of holidays that appeal to you as you age.
My circle isn't particularly unhealthy, either. If your undergoing investigations you can't get holiday insurance, that can knock a few years off your holiday taking.
Grandchildren then come along and need to be planned for.
Have as much fun as you can, in whatever form that is, whilst you don't have to focus on reproducing, or taking care of others.