If the seller also has a mix of albino aneus and paleatum and both are breeding and producing young, they might not even know themselves that they're producing albino variants of two different species. They're not hard to breed, no licence or expertise needed to produce and sell offspring.
If a store, mixed shipments of different species come in all the time, across a whole range of fish. Especially similar looking, very commonly kept species, and they're all being labelled with different common names too. There's no requirement for the wholesalers farming these fish nor the stores to use the scientific names and keep stock strictly segregated.
See? I said Cass would know & she does, with others' input too. Personally, I prefer natural color & fin-shaped fish whenever possible. I dislike the possibility of hybrid fish but it can be difficult to tell sometimes.
Sorry, I didn't make this very clear. What I meant by "they may have both species breeding and not even know they're producing two different species" wasn't that the two species were interbreeding with each other and hybridizing!
What I meant was, and as can easily happen if it's a home breeder, is they have a big group of "albino cories", and may have both aenea and paleatum males and females, breeding within their own species. So male and female aenea spawning and producing viable eggs, and at the same time, male and female paleatum spawning and producing viable eggs. They may not spot the differences and realise they're producing and breeding albino variants of two different species.
Not that they're interbreeding and producing hybrids - although some species that used to fall into the category of "corydoras" can hybridize, so it is an issue to be aware of when stocking mixed groups, and why the Latin names and ID'ing the species is important too.
But in our hypothetical hobbyist tank with mixed albino species breeding - have to consider that especially since the fish are likely being conditioned on the same diets, prompted to breed by same water conditions and things like water changes, so encouraged to spawn at the same time by the same pro-spawning conditions - but also that one species spawning releases hormones into the water that often encourages other species to spawn.
Breeders trying to encourage spawning in a trickier species sometimes use this fact, and can use water from the tank, or co-mingle species, and use the more easily prompted to spawn species and the activity and hormones they release into the water, to try to encourage the trickier species to also spawn.
Hope that helps clarify what I meant!