On top of that, not all sheep are made for wool. Some are made for milk and meat . So they could be sucking some sheep tiddy. Ewe amirite? Haha.... i'll see myself outI'd put money down that the original reasoning behind having sheep was to blend with the alpaca fiber.
Blending different fiber types can alter the properties of the yarn created. 100% alpaca yarn is very elastic, and hard to reshape; it is also incredibly insulating (to the point of overheating, sometimes). Not necessarily great for constant wear garments, moderate climates, etc. Throw some sheep wool in the mix and your yarn is less elastic and a bit lighter, while still maintaining that alpaca softness.
However, as the tranch has clearly shown in the past- they have no self control and no regard for animal husbandry or quality of life, so a couple of sheep to potentially make their yarn more marketable is now "awww, lambs are cute so more must be better".
As a side note- have they ever mentioned what type of sheep they have? Different breeds have different wool types; given their history of poor planning, I'm sure they didn't even consider or research wool types.