This work focuses on the impact of sharing contexts on
consumers’ decision processes and purchase-amount
decisions. Four studies, using both hypothetical and real
(incentive-compatible) choices, find that people regularly
purchase more in sharing (vs. non-sharing) contexts.
Evidence is presented suggesting that a significant portion
of this effect is driven by a cognitive bias arising in sharing
contexts that focuses people on what they will give to
others, and away from what they will receive from others.
Consequences of this bias include the noted surplus in
purchase amounts, over-consumption, and waste
