Issues with DropContact Charges in Email Enrichment Process

I just ran a find work email waterfall enrichment and I noticed that I got charged for 356 rows of DropContact (712 credits) when only 145 of those had an email that DropContact found. The rest charged 2 credits because DropContact "enriched" the contact. Took a closer look and it seems that the DropContact column is being classified as "successful" because the enrichment is for enriching person, not finding email. I'm removing DropContact from future find email waterfall enrichments but this seems like an unnecessary problem. Is there something I'm missing?