It's one of the reasons advocates for the poor often seem to speak a different language to their opposition.
If you live in median-and-above-land, you think of all costs existing on a spectrum. Fancy dinners for $100 on one end. Rice and beans for pennies at the other. This is true for clothes, smartphones, furniture... lots of things. There's a spectrum with options all along it.
It is not true for housing, transport and a lot of other, unavoidable expenses. Housing is the extreme example. Say an average smartphone is $350. $700 buys a luxury phone. $175 gets you an decent phone. Say median rent is $1500. Going above $3k will get you a palace and $750 probably doesn't get you anything. Quality, below median prices is on an extremely steep curve.
Household economics are just completely different below and above a certain threshold... and this has gotten more pronounced over the last generation or two.
Ireland has/had a whole literary genre of stories about miserable poverty-stricken childhoods. They paint a very vivid picture. If you compare it to poverty today, besides being less harsh, it's quite different. They had housing. It was basic, often insecure, but they did have housing.
Food was scarce. That's no longer the case. Stuff though... they had no stuff. No bed, no mugs, no shoes, no pencils. Getting these things was an epic mission and served as a landmark. That is all changed now. Stuff is extremely abundant. Basics like housing and transport are almost as scarce as they were in the bad old days.
The upshot of all this is that we underestimate how poor poor is.