Long before R.F.K., Jr., promised to “Make America Healthy Again,” wellness influencers were peddling a seductive promise of purity to the desperately sick.

Retailers ranging from titans like Amazon and Walmart, down to local small-town shops work very hard to land their share of that business. Sadly and inevitably—so do criminals and scammers.

It’s just easier to go with one of your most common passwords, am I right? Maybe you’ll include the word password in there—no chance of forgetting that!—and 123 if numbers are required. Or perhaps you ...