You can create a filter for the report to weed out the $0 transactions:
  1. Edit the report in question
  2. Go to step 5. Configure Filters
  3. Create a Filter
  4. Select "Valued Transaction" from the drop-down
  5. Set the following drop-down selections: Net Transaction Amount Is Greater Than $0
  6. Click Add this filter

This filter should remove the $0 from the report.