I just submitted a suggestion feedback to SQL Server development team.

It is very bad for the user to be forced to see measures under their physical measure groups. There are a lot of reasons for which a customer would like to see measures organized in different folders.

The most important is related to distinct count measures: each time you define one distinct count measure, a new measure group is created. This physical definition has nothing to do with logical grouping of measures.
Display folder is useless, because it defines only a subfolder under the measure groups.

A possible workaround (define only calculated measures as visible items for the end user) has an unacceptable limitation: you loose the ability to drillthrough cells.

A fast workaround could be to enable the drillthrough, offering a way to define for each calculated measures the corresponding cube space to drillthrough.

A better solution would be to decouple the logical presentation of measures from the physical implementation of them.

If you agree with my suggestion, please vote the "Change measures display: decouple them from measure groups to the client" and the "Enable drillthrough on calculated measures" suggestions (follow the links).

If you don't agree.. well, you never had real users really working with distinct count measures! :-)