"A nearby liquidation firm was selling 2,000 “pandemic packs,” leftovers from a defunct company. Each came with 50 face masks, four small bottles of hand sanitizer and a thermometer. The price was $5 a pack. Mr. Colvin haggled it to $3.50 and bought them all."

"He quickly sold all 2,000 of the 50-packs of masks on eBay, pricing them from $40 to $50 each, and sometimes higher. He declined to disclose his profit on the record but said it was substantial."

$100,000 gross revenue ($50 each), let's say shipping, fees, and price variance were 25%. That's still $75,000 for a $7,000 investment. 10x returns.

It also mentioned them making tens of thousands of dollars in profit in a short time.

That’s because his business is inefficient. If he had left the products in place there wouldn’t be a scarcity in his local region that he then could profit from. He helped create the scarcity, and then profited from it.