Single mum here (and nurse working FT). My parents (born in the 30's and 40's) were wealthy but we always passed clothing on to cousins or younger siblings - and stuff handed to us from older siblings/cousins. My parents didn't like waste, and their parents were the same. My mum made and mended a lot of clothes for us too (often would use fabric from pre-loved things), but she was a very talented seamstress. "New outfits" from shops, were a rarity: we might get these as a present at Christmas or Easter. We were always clean and neatly turned out for school or special events...but we could play in the mud/climb trees etc without getting in trouble for trashing "smart clothes". My parents didn't care for designer clothing, massive houses, expensive restaurants or flash cars: education (ours and that of others - they helped many people back home who wouldn't have been able to get a solid education) was their thing, and hobbies/cultural things too. School shoes (which would double up as "smart shoes") and underwear we got brand new. We also got new things if hand me downs were outgrown.
Now I'm a parent, I do similar. I don't have anywhere near the income my parents (now sadly RIP) had, but me/relatives/friends pass things on/share things, look in charity shops or eBay (rather than buying new) etc. For ourselves as well as our kids. Just because something is secondhand, it doesn't make it bad, ill-fitting or tatty, you can get some lovely things. I don't let my kids run around in torn/worn out/poorly fitting shoes and clothes. I put aside money (or save money up) to afford school trips for the kids and educational things. We don't go overseas for holidays, but will do lots of camping trips in UK. I will pay for us to go to the theatre/opera/gigs when tickets aren't expensive. My eldest has a cheap gym membership, my youngest has swimming lessons. When the kids get to the same size as me for shoes or clothes, I buy more expensive ones (then I can have them once the kids outgrow them!). Example: When DC1 was younger, I got him some Birkenstock sandals (he wanted some): I bought the real deal as he was the same size as me. When he outgrew them, I had them. When DC1 was little, I bought him a lovely winter coat that went to my friend's kids when he outgrew it....and then passed back to my youngest, and now passed to another friend's youngest. Five different kids have got good use out of it over the years, and it's in perfect condition still. We do the same with toys and books. I used to cut the kids' hair myself when they were younger. Now my eldest will go to a barber as he prefers the styles they do but my youngest likes me to trim her hair. I get my hair cut as I can't do it myself and the kids are too scared to try trimming it!! I don't get my nails done, I don't wear makeup often. I don't have beauty treatments or posh lunches. I rarely buy or drink alcohol and I don't smoke. Eating out is a rarity, as I'm lucky enough to be able to cook/make things at home. Food shopping will vary: I don't buy all my groceries in Lidl or Aldi, and I definitely don't buy it all in Waitrose or M+S!! It will vary according to what I find better quality and isn't going to break the bank!
Neither my parents, nor my friends, nor I, are trying to pretend we're poor. We're all very lucky to be able to afford a roof over our heads, heating, food. We're just trying to reduce spending, reduce waste and help each other out. Kids grow so fast, so if we were to all buy new things ( even if cheap), then that would still cost quite a bit.