TL;DR version - Laundry Detergent is pretty fungible, everyone needs it, and its difficult to trace, unscrupulous retailers will buy stolen tide for cash.
This situation provides crooks with a couple of benefits, one they can separate the money trail for selling drugs, after all who thinks this looks like a drug buy:
Alice goes to grocery gets laundry detergent;
Bob sells stolen detergent to a grocery for cash.
No way to connect Bob and Alice until you add: Alice goes to grocery gets laundry detergent;
Alice gives Detergent to Bob for drugs.
Bob sells stolen detergent to a grocery for cash.
Now you can connect them and see the drug deal. Hard to get a warrant to search Bob's car for laundry detergent.