The Zip Code report will show sales for all sales methods, this includes Online sales. Since daily admissions are counted for the day they are bought, they can appear on the zip code report even if no one has attended an event on that day.  You can check id this is where the sales are coming from by using the filters on the zip code report. 

1. Go to the sales page
2. Under reports go click Zip code report
3. Select the day filter to match the day you are seeing sales for
4. select to see All sales methods  and click run report 
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4. Go to the Totals area of the report.
5. Look at the number of visitors 
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6.Go back to the sales method filter and change it to online sales.
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7. Run the report. 
8. Go to the totals are of the report, and see that the two match and all sales were online sales.
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