"Gary Drescher" wrote in message
news:kS6vc.27832$3x.24720@attbi_s54...

How does that reply address the question it's replying to?


Sorry, I don't see how I can state it any simpler.



In essence, the
question has to do with how we quantify the "things they use"--in
particular, is the marginal cost the right measure?


Yes.



You're proposing that
it is the right measure for "distinct" groups, but not for groups that
are not very "distinct" (such as in my analogy). What I'm wondering, and
what you have yet to address, is why you think a group's "distinctness"
has
anything to do with whether marginal cost is the right way to quantify
what
they "use".


Because to do it any other way would require a group to pay for things they
do not use. Everyone should pay their own way. Don't you agree?