Matt Ryan posts about the banning of peanut butter in schools.

It seems to me that if transactions costs are low, it shouldn't matter who gets rights to the school environment. Even if rights are given to those with the allergies, they might be willing to give up certain considerations for other concessions. If the value that all other students get from eating peanut butter is greater than the value those with allergies receive from an outright ban, they should be able to bargain to the efficient solution. Thus in terms of efficiency, it would seem not to matter what the rule is on peanuts in school.

Transactions costs are probably really high, however, since social norms likely prevent any post-rule bargaining. That is likely why we see such fights over the initial assignment of rights.

At least that's my thinking on the issue. Any others?