A restaurant chain adding locations expects advertising to get cheaper per store, since one campaign now covers more doors. In practice the cost per store often rises, and the reason is how American media markets are drawn.
Media markets are fixed shapes
Broadcast and much local media in the United States is sold by designated market area, a fixed geographic unit built around a metro's television signal. A brand buys the whole market or nothing.
A chain with twenty stores inside one market spreads that cost across twenty locations. A chain with four stores in a new market pays close to the same price for a quarter of the return.
Which means expansion moves a brand from an efficient position to an inefficient one, and stays there until store count in the new market catches up.
The gap between footprint and coverage
Store footprints follow real estate opportunity: an available site on a good corner, a lease that came free. Those decisions rarely produce a tidy cluster inside one market.
The result is a chain with stores scattered across several markets, none of them dense enough to justify market-wide buying. Advertising has to be bought at a scale the store base cannot support.
Chains that grow deliberately fill a market before entering the next, which keeps media efficient. Chains that grow opportunistically pay a penalty they only see in the marketing line.
Why digital does not solve it cleanly
Digital targeting can draw a radius around each store, which looks like the answer. The catch is that small radius audiences are thin, and thin audiences get expensive fast.
Bidding into a narrow geography puts a brand in competition with every other advertiser wanting that same small pool. The cost per thousand climbs as the target shrinks.
So digital reduces waste without eliminating the underlying problem, which is that a few stores cannot amortize a serious media presence anywhere.
The temptation to spread the budget thin
Faced with several under-served markets, the common response is to divide the budget evenly. Every market gets something, and no market gets enough to register.
Advertising works on repetition within a defined audience. Spending below the level where repetition happens produces awareness that decays before it reaches a purchase decision.
The harder choice is to concentrate, funding one or two markets properly and letting the others run on local tactics until they have the store density to earn a media budget.
What the store-level numbers hide
Averaging performance across all stores masks the split. The mature market carries the average up while the new markets sit well below it, and the blended figure looks acceptable.
Splitting reporting by market makes the pattern visible immediately, and usually uncomfortable. New markets almost always underperform for longer than the expansion plan assumed.
That is not a failure of the campaign. It is the cost of entering a market before the store base is large enough to pay for reaching it.