I develop a rather simple agent-based model to capture a co-evolution of opinion formation, political decision making and economic outcomes. I use this model to study how societies form opinions if their members have opposing interests. Agents are connected in a social network and exchange opinions, but differ with regard to their interests and ability to gain information about them. I show that inequality in information and economic resources can have a drastic impact on aggregated opinion. In particular, my model illustrates how a tiny, but well-informed minority can influence group decisions to their favor. This effect is amplified if these agents are able to command more economic resources to advertise their views and if they can target their advertisements efficiently, as made possible by the rise of information technology. My results contribute to the understanding of pressing questions such as climate change denial and highlight the dangers that economic and information inequality can pose for democracies.