It’s a better definition of luxuries.

If someone is spending more on food, clothing, electronics as their income rise those things are clearly discretionary.

A rational actor defers maintenance when money is scarce. That doesn't make maintenance discretionary, just deferrable and indefinitely deferred maintenance eventually causes unavoidable, huge spending.

Or just loss that doesn't manifest as spending. E.g., deferred health maintenance eventually causes death.

It's a definition that works for how economists talk about things, but is extremely out of phase with the colloquial definition. Hence the stated outrage from the parent on how the poor spend so much of their income on "luxuries", when that refers to different things than what most non-economists would define as "luxuries".

No it's not. Poor people live in food deserts and buy 5000 calorie dinners for $2 at Dollar General. It's hardly discretionary to try to feed yourself real food. Now let's tie in the cost of healthcare associated with eating cheap junk food and you've got a problem. This is like an argument with someone who denies global warming.

Unless someone is starving, spending more on food as income rises is discretionary. A proper food budget is stable, it should not change as someone earns more money.

As someone who ate well on minimum wage, you’re not going to convince me low-income families can’t afford food in America if they’re properly budgeting.

I’m amazed that your personal experience was so representative that you don’t even have to consider that other people’s circumstances might be different.

As of 2012 food costs as a % of spending are the lowest in the US than anywhere else in the world. [0] During the Obama administration there was a massive increase in enrollment with the SNAP program. [1] Between government programs and charitable organizations I'd argue it is practically impossible for someone to go hungry through no fault of their own. You'd have to be unlucky on a cosmic level.

[0] http://www.ibtimes.com/us-spends-less-food-any-other-country... [1] http://www.trivisonno.com/food-stamps-charts

There’s a wide range of diets between “not literally starving” and “eating a nutritious and healthy diet.”

To abuse the phrase, anecdotes are not data, unless they're your own.

> Unless someone is starving, spending more on food as income rises is discretionary

It's also not discretionary if at lower income levels they receive a greater share of direct food aid that isn't counted in their spending because they never exchange money or a money-denominated voucher for it.

> As someone who ate well on minimum wage, you’re not going to convince me low-income families can’t afford food in America if they’re properly budgeting.

Many of the poor:

(1) Aren't able to find work (and may not be able to work; permanent disability is a thing, and positively correlated with poverty),

(2) May not work find full time work when they work, and

(3) May be supporting non-working (and unable for age or other reasons to work) dependents on their part-time, intermittent, minimum wage income.

If you don't mind me asking, how long ago was your experience with minimum wage? Also, did you have access to a store where you could purchase fresh fruits and vegetables?