I think in the USA there is a warning on the box that says “don’t hit your thumb”
Yes, they can. But atisket is adding releases from these specific stores. So the data it has to hand cannot predate the store.
In those much rarer cases where a digital release pre-dates iTunes\Spotify\etc then the date can be manually corrected. If someone has other data to hand they can update the release. But this is not the case here. The majority of these are just using CD\vinyl release dates.
This is also why I suggest it is atisket that should limit the date ranges submitted, and not MB itself. 