What can cause an Index "total writer" to be the same in every index?

I have a table, with some Indexes ( created by me, others by SQL Server Profiler (SqlServer 2008)).

I use this query to analyze unused Indexes:

--Possible bad Indexes (writes > reads)
SELECT  OBJECT_NAME(s.object_id) AS 'Table Name',
        i.name AS 'Index Name',
        i.index_id,
        user_updates AS 'Total Writes',
        user_seeks + user_scans + user_lookups AS 'Total Reads',
        user_updates - ( user_seeks + user_scans + user_lookups ) AS 'Difference'
FROM    sys.dm_db_index_usage_stats AS s WITH ( NOLOCK )
        INNER JOIN sys.indexes AS i WITH ( NOLOCK ) ON s.object_id = i.object_id
                                                       AND i.index_id = s.index_id
WHERE   OBJECTPROPERTY(s.object_id, 'IsUserTable') = 1
        AND s.database_id = DB_ID()
        AND user_updates > ( user_seeks + user_scans + user_lookups )
        AND i.index_id > 1
ORDER BY 'Difference' DESC,
        'Total Writes' DESC,
        'Total Reads' ASC ;

But what I see, is that 14 Indexes ( yes i'm studing to disable them ) have the same "total writes". If I hold F5, i can se that they're used in "writes" at the same time.

Total reads are different.

What is the reason of this? why every index is updated ( write ) at the same time and same ammount, But with different reads?

Didn't found anything like this on web or stack.

Thanks