People like to believe they make rational choices; but we’re not calculators – we’re comparers.
We rarely ask “Is this a good price?”
We ask “Which of these feels like the best value?”
That’s the behavioural gap McDonald’s quietly exploited.
By redesigning its menus and pricing, it shifted perception – and made millions of people buy more than they intended to.
The Behavioural Problem: Low Spend, Flat Margins
McDonald’s doesn’t make its margin on cheeseburgers: it makes it on size upgrades and combo structures.
But upselling isn’t always persuasive. In fact, customers often push back on being “sold to.”
So instead of using pressure, McDonald’s used perception and changed how people felt about the value of an upgrade.
The Intervention: Use Anchoring and the Decoy Effect to Frame Choice
McDonald’s implemented a pricing strategy based on two behavioural tactics:
1. Anchoring
When people see a higher price first, the next one feels like a better deal – even if it’s still high.
By listing larger meals and premium items up front (or in the middle), McDonald’s shifted the anchor for what a “normal” spend looks like.
2. The Decoy Effect
Also called asymmetric dominance, this is when a third option is introduced to make another option look more appealing by comparison.
Classic example:
- Small: £1.50
- Medium: £2.40
- Large: £2.50
The medium is a decoy: its price is too close to the large. So the large feels like a better deal, even if it’s more than you planned to spend.
Result? You upgrade – not because you want more food, but because you don’t want to lose value.
The Behavioural Principles: Framing, Loss Aversion, Value Perception
This tactic works because:
- We hate overpaying (loss aversion);
- We prefer relative value over absolute price;
- We’re influenced by context more than content.
People didn’t walk into McDonald’s wanting a large. They walked in wanting to feel smart.
McDonald’s made sure that the larger option felt like the better choice – even when it wasn’t the best fit.
The Result: Predictable Upsell Behaviour
McDonald’s increased:
- Average spend per customer;
- Combo meal uptake;
- “Supersize” upgrades (before retiring the term post-documentary era).
It trained customers to think in value bundles, not individual items.
Even today, the behavioural design lives on in every self-service kiosk, app order, and drink fountain – each optimised to frame your decision just enough to tilt it upward.
The Takeaway for Business
Your customer’s decision isn’t happening in a vacuum – it’s happening in the frame you built.
- Are you using anchors to guide value perception?
- Are you introducing decoys that shape spend?
- Are you designing pricing as a choice architecture – not just a spreadsheet?
You don’t have to change what you offer. You just have to change what it’s compared to.
That’s how small behavioural nudges lead to big commercial outcomes.
