With the purchase, it seems more like splitting the surplus. It does benefit you to have a store nearby that sells things at a lower price than you would have to pay in total by going to the less convenient store. The question is, how much of that gain is being captured by the store owner, and how much by you? If you think that they are capturing “too much” of the gains by the prices they set, then it can be rational to refuse the offer (just as in the Ultimatum Game).
One question is whether they can provide enough evidence that the division is reasonably fair. Maybe it is! There may be legitimate costs or extra risk that the local shop owner incurs versus the alternative.
Another question is what the other potential customers are likely to do. If most of them will shop there even when the owner is capturing 80% of the surplus and leaving the customers with only 20%, then it is likely not in the owner’s interest to lower the prices much below 80% surplus capture. If the other customers are likely to recognize when the shop owner is capturing too much surplus (as would happen in dath ilan), then it may not be worthwhile to set the prices higher than 50% capture.
With the purchase, it seems more like splitting the surplus. It does benefit you to have a store nearby that sells things at a lower price than you would have to pay in total by going to the less convenient store. The question is, how much of that gain is being captured by the store owner, and how much by you? If you think that they are capturing “too much” of the gains by the prices they set, then it can be rational to refuse the offer (just as in the Ultimatum Game).
One question is whether they can provide enough evidence that the division is reasonably fair. Maybe it is! There may be legitimate costs or extra risk that the local shop owner incurs versus the alternative.
Another question is what the other potential customers are likely to do. If most of them will shop there even when the owner is capturing 80% of the surplus and leaving the customers with only 20%, then it is likely not in the owner’s interest to lower the prices much below 80% surplus capture. If the other customers are likely to recognize when the shop owner is capturing too much surplus (as would happen in dath ilan), then it may not be worthwhile to set the prices higher than 50% capture.