Because these companies have large legal departments essentially in charge of minimizing regulatory and reputational risk. It's the same reason they've been progressively cracking down on firearm accessories, BB guns, knives, fireworks, laboratory chemicals, erotica, pill presses, and a bunch of other things over the past 20 years. All of that is generally legal in the US but makes lawyers and PR people queasy. It's not just marketplaces, Paypal has asinine rules on what you can and cannot pay for. So does Google Pay, Zelle, Venmo, and so on.
I don't think it's useful to point out inconsistencies; the bottom line is that lasers will be on the chopping block within our lifetime too.
I don't think it's useful to point out inconsistencies; the bottom line is that lasers will be on the chopping block within our lifetime too.