While a table in that report was referenced, that table’s data was not cited for a reason: it was from Statistics Canada’s Survey of Household Spending (SHS). That table shows that Canadians in the bottom income quintile (lowest 20% of income earning households) spent 16.3% of their household expenditure on food, while the top income quintile (highest 20% of income earning households) spent only 7.5% of their household expenditure on food.
Those figures in and of themselves dispel the inane theory put forward by economists Michael Smart and Jack Mintz that the wealthy benefit more from the government not taxing food staples (they rely on the intellectually dishonest method of looking at gross instead of share of expenditure on food). That said, the SHS data still doesn’t give an accurate picture of the disparity in terms of food security stemming from income inequality.
How come? While the referenced SHS table separates families by income quintile, it reports food expenditure as a share of total expenditure, not income. This is well-known, and the parameters of the SHS actually factors a significant difference, 30%, between income and expenditure into the data, as noted in the referenced Spending Patterns (PDF) report:
…This important quality control tool involves the balancing of receipts (income and other money
received by the household) and disbursements (total expenditure plus the variable Money flows—assets, loans, and other debts) for each questionnaire. If the difference is greater than 30% of the larger of receipts or disbursements, the record is considered unusable and therefore will not be used.
The variable that makes a significant difference in terms of share of income between the top and bottom household earnings quintiles: investment income. If one were to look at food (or any other current consumption items) as a share of income, and investment income was included, the increase in the denominator for the highest income households would significantly reduce their share spent on food and other current consumption items relative to the lowest income households.
Average household income before tax
This includes total household income received in the reference year, income from wages and salaries, self-employment, net rentals, interest and dividends, all pensions, workers’ compensation and employment insurance benefits, social assistance and income supplements, child tax benefits, goods and services tax credits, harmonized sales tax credits, provincial tax credits and miscellaneous regular income receipts. (Notably, capital gains are excluded)
For the purpose of the SHS, this means very wealthy households with a) household expenditure 30% less than reported income or b) whose primary revenue source is investment income (which isn’t counted) resulting in household expenditure appearing to exceed by more than 30% reported income, are effectively excluded from the SHS. So it’s not really a comparison between the highest and lowest, but rather high middle and low-income households. The SHS methodology effectively masks income and food security disparity by excluding the highest income earners.
There are a couple of issues with counting investment income, the main one being the challenge of distinguishing wealth from income. Historically, there hasn’t been much of an effort to address the issue, at least not in Canada’s household survey programs. The 2011 Census would have asked Canadians to report capital gains for the first time, in addition to dividend and interest income. While the question was retained in the 2011 National Household Survey (NHS), households that had substantial capital gains and did not wish to report them could have opted not to respond to the NHS at all.