Once a course is done and WGT has recouped its costs from the first several thousand players, it makes a healthy marginal profit from each additional player who tees off.

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It can generate some marginal gross profit, thus making the medicine slightly cheaper for all, and it makes the world healthier all around, too.

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Marginal cost begins to exceed average cost, creating a profit margin despite competitive pressure to price to marginal cost.

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Much of the development cost of a new drug is paid by the US market (yes, this is why you pay higher prices than most Europeans do) meaning that as long as drugs in, say, Greece are sold at above the marginal cost of production they still make a profit.

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This contributes no profit on the first visit unless the marginal cost is very small or the discounted product pulls through other profitable sales.

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The company should already be charging the most it can for that marginal phone call and a change in sunk costs might affect accounting profit but not that revenue maximising price charged.

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