It's due probably because there are multiple values that could be associated with each Dimension. And Tableau doesn't know which one of those values to display.
Please see this reference: Aggregating Data The asterisk (*) is actually a visual indicator of a special type of Null value that occurs when there are multiple values.
For example, you have Markets on the primary column as a Dimension, but the following column Dimensions have an asterisk, meaning there are probably multiple owners, multiple channels, etc., which it cannot display in the context of the view you have. It can summarize your other values such as numbers without issue, which it did.
Hope that helps! Don