It's not like online retailers don't exist. Well, for now. They _will_ go under if we just let Amazon run everything unchecked.
What matters is that we provide an environment within which we can trade amongst each other as (relative) equals, not one in which the Great Overlord owns all of the means of production.
This isn't a border dispute, this is about behaviour within a country.
Forcing the adoption of exploitative labor practices is helpful to consumers within that jurisdiction?
The problem is that a massive company essentially owns online commerce, anti-trust legislation should be addressing this and somehow it's not. Let them own a few % of the market, don't let them literally take over.
I understand your concern, but the reason that anti-trust legislation is not addressing this is that there is frankly no monopoly here.
[1] https://de.statista.com/infografik/16018/marktanteile-von-am...
The current percentage is almost irrelevant anyway, the endgame of this is monopoly whether or not they have it right now, the vertical integration of delivery alone is enough.
I'd split up the major supermarkets as well FWIW, but that's a different discussion.
We don't need what is essentially a monopoly, or at least targeting becoming a monopoly, controlling internet sales. It's not beneficial. It may have been in the very short term, but now the effects of pushing out small businesses are clear, we can just not have it.
The labour practices are almost besides the point, anti-trust should break them up.