One study of four US cities found that overall advertising density was two- to four-times higher in low-income postal codes than in high-income ones. This is in large part because the land there is cheaper. Wealthier areas are also more likely to be deemed to have conservation or heritage value, and so it’s harder to obtain planning permission to erect ads there. Privately owned sites will generally have an easier time obtaining such permission, unless especially motivated or politically connected citizens mount opposition to it. In the UK, the exact procedures vary from council to council, although the National Policy Planning Framework sets out general stipulations.
Less affluent areas (for instance, in Newcastle, England) have more dense concentrations of billboards for less healthy foods. The Newcastle study found that 20% of the advertising land space was for food, with a KFC product being the most commonly advertised food. As Adams