This is one of my bigger questions, lately. There is so much we can (and do) do without, easily.
Some things, clearly bring enough pleasure, or convenience that their cost is well worth it. Other things, it's not as clear.
We definitely needed more book cases. Found some great bookcases, with a fun history, great beauty and cham, etc. Fabulous purchase, imo. We've made some other recent purchases like that: they fill a need, and they do so while bringing a certain level of pleasure.
But now there are some other things, that I feel slightly hesitant, because they don't actually serve any need, like a bed. We've been married for many years, and we've never had a bed. We have a mattress and boxsprings, on the metal frame. So we've never had a headboard or footboard, etc. We've recently seen some beautiful beds. Great wood, fabulous workmanship, the kind of piece that you know will survive to be a beautiful, valuable antique one day. Good value, even, considering.
But come on, we've never needed a bed. Sure, we always figured we'd eventually have nice looking wood at either end of our mattresses, but now that we're really looking into it, it seems kind of silly. Despite the incredible value of the furniture itself, the frugal person in me says, "but it doesn't serve ANY purpose!" All it is is beautiful. And so I really question how much joy I will really get out of something beautiful in my bedroom, that costs so much. If you ask me, would I spend that much on a painting to hang on the wall...highly unlikely. Would I spend that much on a beautiful knick-knack? I couldn't imagine it.
But there's the little nagging thing that one "ought" to have a bed. I don't know why headboards and footboards are so common, but they are. And a part of me wants one too. It just also seems so silly.