I'm dubious that huge bottles of Tide detergent are being used as currency in any meaningful way. Pretty much every article I've seen about the subject sources back to the New York Magazine article you linked. Not one article mentions what drug dealers do with the gallons of Tide they receive in exchange for vials of rocks.
Here's my guess as to what's happening and why a cashless system would mostly end this practice too . . .
There's a modestly sized black market in high priced consumer products like Tide detergent, Gillette razors, etc. Those products are targeted by thieves because they can re-sell a $20 bottle of Tide for $5 on the black market to consumers who use the products or to unscrupulous stores that re-sell them at slightly discounted prices.
And because there's already an active black market in these products there's a street price for them. Some drug dealers with connections to that black market may be willing to trade drugs for Tide because they can monetize Tide in the black market.
That system works only as long as there's a large enough black market for Tide to accommodate the demand for drugs. I don't think it's a stretch to say that the market for drugs is many, many, many times larger than the market for black market Tide. With that in mind I don't think it's a stretch to say that Tide as a currency for drugs is a vanishingly small part of the market.
And unless you increase the size of the black market, you can't increase the volume of trade denominated in bottles of Tide. There's no reason to think electronic commerce is going to increase the size of the black market.
On the contrary, it's far more likely that the black market would shrink in a cashless system because those unscrupulous store owners who monetize the majority of the stolen Tide would have no record of ever paying for their inventory. It would be easy enough to close them down.
Moreover, no one else would be able to "launder" their Tide and turn into cash either. And without an ability to turn bottles of Tide into a widely accepted from of payment it would be worthless as a currency for drugs or anything else.
Strike another victory for cashless over crime!