Why can the target of the OUTPUT INTO clause not be a view?
From MSDN - Output clause:

"The OUTPUT clause is not supported in the following statements:


DML statements that reference local partitioned views, distributed partitioned views, or remote tables. 
INSERT statements that contain an EXECUTE statement.
Full-text predicates are not allowed in the OUTPUT clause when the database compatibility level is set to 100.
The OUTPUT INTO clause cannot be used to insert into a view, or rowset function.
A user-defined function cannot be created if it contains an OUTPUT INTO clause that has a table as its target.
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