[cdecl]

The difference is that often, particular things are more concretely defined. A ban on advertising might be so onerous you wouldn't even be able to 'advertise' your FOSS projects on HN.

In what way could you learn about novel commercial things in the absence of advertising? Word of mouth alone?

[NeutralCrane]

I don’t think it would be onerous nor ill defined. Simply make it illegal to pay someone to or receive payment for making a public announcement for a product, service, or brand. If no payment is involved, it’s fine. People are free to promote their own or others products on social media, YouTube, the side of their car or house, so long as they aren’t paid to do so. That is hardly any more convoluted or ill-defined than dozens of other laws on the books.

And yes, word of mouth and non-paid advertising is absolutely capable of spreading awareness on its own.

[cdecl]

Does giving someone the product count as a payment?

[ajolly]

In the US, yes that would count his taxable income so I'd also consider it a payment.