Going from infecting a lab worker to a high-precision spillover in a wet market, without leaving a trace anywhere else, is just not how a viral infection is likely to work.
> An important feature in this distribution, consistent with earlier findings (4), is that the majority (76%) of infected cases shows no evidence of onward transmission amongst any of their contacts.
https://pmc.ncbi.nlm.nih.gov/articles/PMC7523148/
So there's no reason to expect that the first cluster that generates enough sickness and death to attract official attention will occur near the point of introduction. If we look at North America, then it in fact did not--the introduction must have been at an airport or seaport, but the first large clusters were in nursing homes, church choir practices, etc. This is different from SARS-1 or MERS, which were deadly enough to make that cryptic spread much less likely.
which are not supermarkets.
The conditions for a super-spreader event can arise in many different ways--before the contact tracers gave up, they found clusters in that wet market, those nursing homes, cruise ships, meat processors, migrant worker dormitories, and many other types of venues. I don't see why we'd ever expect the first cluster in the same type of venue in both countries, except by chance.