Why was I charged Cook County, IL sales tax?

Our warehouse is located in Cook County, IL (Franklin Park) and Illinois is an origin-based sales tax state. In origin-based states, sales tax is collected based on where the seller (in this case Dropps) is located. That sales rate includes a combination of state, county, city, and district tax rates.

Cook County / Franklin Park Sales Tax:
State: 6.25%
County: 2.75%
Municipal: 1%
Tax Policy: Do not tax Shipping & Handling

For additional information regarding origin based sales tax:
TaxJar information regarding Illinois as an Origin Based State