Grew up in the 70s, single parent home for the first 9 years of my life and a lot of what you say chimes. New clothes were a HUGE event - mainly wore homemade or from jumble sales. Also had vouchers for school uniform and somehow,I guess because the other kids got to bend the rules more with their choice of a navy skirt but as I was in the regulation hideous nylon A line they knew I was in the "council issued" uniform, so to speak and I was teased mercilessly about this.
At uni in the 90s, it felt much more egalitarian as there were so many interesting different tribes so anything went and I kept this up for a few years but when I was in my first " proper" job I remember being very aware of not having fit for purpose basics - I started to become much more aware that I was what was referred to then as 'working class made good' (through fully funded university grants I was able to enter a graduate profession albeit very poorly paid for the first few year).
Odd, I guess, but I always remember being very conscious of always having to buy from the end of the sale rail etc and never having a decent winter coat or shoes. The class thing wasn't as noticeable at uni as we all lived in crappy student digs, all used our NUS cards for discounts etc - it was really, really unusual for any student to have their own car at uni etc and grunge practically demanded you trawl the charity shop rails.
I love clothes and nice make up/accessories etc and lots of the comments on here echo with me - going overboard at times, then being rather puritanical with wearing things to death or, a habit I have now broken, the dreaded, "keeping things for best" meaning I would save and save to get a really lovely item I wanted and then .... not wear it for ages.
Second hand shopping wasn't cool when I was a little kid and I remember being really embarrassed that all my clothes were either hand me downs (bear in mind I had two older brothers!) or jumble sale finds. My mum really struggled to do her best by us and I can't imagine how hard it must have been. Now I love using eBay, Vinted etc much, much more than high street shopping which just completely overwhelms me. The thought of 'going shopping' as an afternoon activity on the weekend makes me feel a bit sick.