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Basically, _setvar should only be used to set things that you're pretty sure won't be changing too often; say whether the visitor prefers coke or pepsi. The _setvar cookie lasts a long time (last time I checked it was two years, but may be less now) and in terms of how the data is shown in the reports, I'm pretty sure only the first one during a vistor's session counts. I'm actually surprised you're seeing many visits at all in the profile you created; I would expect most of your visits to show up as Anonymouse, as most people are until they log in.
then you could create a filter to just include page URL's that started with /Anonymouse or /Member.