Driving down the road the other day, I noticed something I think few people have considered in a long time - certainly it is not something that many people would think about, nowadays.
Living in a semi-rural area, growing vegetables, trying to get food trees going, having neighbours with cows, horses, or sheep... All these things make you realise that a large, well-kept lawn (free of trees, vegetable patches, or livestock) is quite a luxury...
It wasn't that long ago that a lawn was a luxury that people literally couldn't afford.
You live in a city, you maybe have a small block - if you're lucky. I've known plenty of people who live in suburbs where the only soil you see is around the few trees, tokens of the environment far away.
In suburbia, which really is a comparatively modern invention, you have a small amount of garden available to you.
Out in the countryside, lawn isn't there to be decorative - it is a resource. You either dig it up and grow some of your food there, or you run livestock.
Having a large lawn means that you were not only rich enough to buy all of your food (which is plentiful and available) nor need to have any livestock, but that you have the time to tend to it - or can pay someone to tend it for you. Hence, the English Gentry, particularly the Landed type - plenty of other people to do the hard work for you.
Of course, PSHTF (Post Shit Hits The Fan), a well kept lawn would probably demonstrate a significant mental illness... at least until a post-apocalyptic gentry developed. This, of course, goes double for an underground shelter - if you have plenty of elbow room through out when you move in, you either don't appreciate how much work you will need to do, nor have enough of the resources you need. Or you have plenty of other people there who you believe will do your part of the work for you...
In other words, you are indulging in a luxury you might not afford... Sort of like spending big on the credit card now, and having problems later because you have so much debt to pay off.