Bailey Norwood and I have a new paper forthcoming in the journal Ecological Economics that seeks to identify how much money vegetarians spend on food relative to meat eaters. This issue is of interest because food costs are often a reason touted for reduced meat consumption. The argument is that meat is expensive and thus eschewing meat (or participating in meatless Monday, for example) will save you money. Here additional motivation for the work:
We used data from my monthly Food Demand Survey (FooDS) to determine how much vegetarians report spending on food at home and away from home compared to meat eaters. The analysis is complicated by several factors. First, many of the people in our survey who say they are vegetarian or vegan actually choose a meat item in a prior portion of the survey that simulates a shopping experience (perhaps because someone else in their household eats meat). Thus, we conduct our analysis separately for "true" vegetarians (about 2.2% of the sample) and "partial" vegetarians (about 3% of our sample). Secondly, vegetarians/vegans differ from meat eaters in a variety of ways, such as gender, political ideology, income, etc. This raises the question of whether differences in gender, income, etc. explain differences in spending patterns or whether it is dietary choices. Moreover, while one can change from from a meat eater to vegetarian, one cannot (easily) change from male to female, very conservative to very liberal, or black to white. Thus, we conduct several counter-factual simulations where we ask what happens if one converts to vegetarianism but retains their prior demographic characteristics vs. someone who differs in both regards.
Here are some summary statistics on distribution of spending by meat eating status (not controlling for demographic or income differences)
It appears "partial vegetarians" spend more on food than the other two groups, however, when one looks at the demographics this group is also a bit richer, is more likely to have children in the household, and has larger household size - all things that are correlated with higher food expenditures.
After adjusting for differences in demographics, we continue to find differences in spending patterns, though the differences are typically smaller. Here are some graphs I constructed using the estimates in the paper. The figure shows spending for each consumption group assuming each group has demographics equal to the mean demographics in the sample (i.e., each group has the same demographics) for different levels of income.
In general, richer households spend more on food than poor households regardless of whether one eats meat or not. However, at every income level, partial vegetarians spend more than meat eaters while true vegetarians spend less (assuming same gender, household size, etc.). For example, for households earning between $60,000 and $79,000 per year, weekly spending on food for meat eaters is $156, for partial vegetarians its $196, and for true vegetarians its $116.
Here is the same result expressed as a share of income (these are the so-called Engel curves).
Meat eaters in households earning between $60,000 and $79,000 per year spend about 11.6% of their income on food for partial vegetarians at the same income level it's 14.5%, and for true vegetarians it 8.5%.
Of course, these three groups don't have the same incomes. The percent of respondents living in households making more than $100,000/year is 11.3% for meat eaters, 18.3% for partial vegetarians, and 14.4% for true vegetarians. Thus, if one adjusts for differences in household income, some of the differences shown in the above graphs disappear.
Here is a summary of what we found.