Spain, with one of the highest unemployment rates in Europe (and one of the lowest birthrates), won’t even pretend these people will contribute anything. Spain is now to Europe what Mexico is to North America, sending their youth north(east) to work in Germany and send back remittances to the remaining Spaniards. These immigrants don’t speak Spanish, and simply have no role in Spain; they don’t need non-Spanish speaking “Mexicans” (just as the US doesn’t, either).
They also won't contribute anything to these people, which is why they will most likely keep right on going to France or Portugal.