At least in Spain, it's common to see strawberries with unmarked origin or, even worse, "Origin: Spain" but it happens to be a Spanish company that brings them from Morocco and only does the packaging.
(BTW, not sure if each of these things is legal or not. But the fact is that they happen. I would be happy with actually enforced laws that mandated specifying the actual origin of everything).
They still need some of the product to come from the EU to be able to claim "EU", but if they don't go through the effort to write on the packaging which parts come from where, the product is possibly mostly non-EU, yes.. :-P
And you can put your money on it that they have lobbied hard so as not to have to put the exact countries of origin on their packages. All under the "That would make the packaging confusing for consumers" guise. Or the "Our product chain is too complex, and that would be very inconvenient" guise..
The import switch trick exists, but is nonetheless illegal. So is mislabeling food origin (even from within the EU). For instance, I know that the health authorities in France go to open-air markets and road-side stalls to check that produces have labels, and that the country of origin is correct. (EU onions, as an example, is not an appropriate labeling. Nor is labeling Italian onions as regional onions..)
Of course, the local authorities might not have the will or incentives to strictly enforce your consumer rights..
Blueberries, same thing, but they are free from the forest.
Of course, strawberries won't be whole and firm once they are frozen with some sugar, but the taste of summer is there.
Depending on your location there's a decent list of plants you can grow for practically zero maintenance that will produce more of that food than one family can consume, forever. Some of them are way more work to remove than introduce.
Its harder and harder, but if one really cares in Europe, you have to focus on well-known brands (or whole supermarket chains if you have those) that have long term reputation to uphold.
Here in Switzerland its a bit easier (and EU food products are generally viewed as subpar), but you pay, and you pay a lot.
At the end, you get what you pay for, and there is not that much room for too-good deals which are not scams in some way. And prepare to just don't buy stuff if you don't find suitable things, and replace with something else. And focus on seasonal local stuff as much as possible (I guess residents of say Trondheim are casting a dark look on this)
However, in spite of the blandness and the working conditions problem you mention, I do trust Spanish fruit to generally not have hepatitis A or EU-banned pesticides, so I'd still take it over Moroccan imports any day, at least if I am given the information to choose.
(Not that you can trust any small fruit store either... but some are good).
https://www-consumer-es.translate.goog/seguridad-alimentaria...
If by chance you go to an street market and you don't see or trust labelling you can go or ask. Any other place origin is properly labeled. Of course not only for vegetables and fruits but also for fish, seafood and meat.
In practice, the supermarket where I typically buy (because it's closest to home) is hit and miss. Sometimes they specify the origin, sometimes they don't. I'm sure if I asked they would tell me, but the process would probably involve an overworked cashier asking an equally overworked manager, plenty of waiting, making other customers wait as well, and being seen as the nitpicky guy who is always asking. Ideally it's what we all should do, but in practice I and most people I know have no time or willpower for that.
On the other hand, in small fruit stores and markets, the overwhelming majority of the fruit doesn't specify origin. I can ask and at those places I will probably get an immediate answer, of course. But then I have to trust the word of someone whose primary motivation is to sell me the fruit. My bet is that many wouldn't acknowledge it's from Morocco. And it's not like I can check.
If it were so easy, newspapers wouldn't be publishing "tricks" to try to identify Spanish fruit:
https://www-elespanol-com.translate.goog/cocinillas/actualid...
https://www-larazon-es.translate.goog/sociedad/asi-puedes-co...
Tricks that sadly aren't even guaranteed to work, because a Spanish company selling fruit from Morocco can use a Spanish barcode.
Apples, peaches, grapes and oranges are also high up on that list..