[GopherGOPer]

Yes you can buy them out of a Catholic supply catalogue, but they are still made by the same Monks and Sisters. Commercially(supermarkets) do not carry them, and they are not meant for use outside of those wishing to use them for Mass.

Out of the same catalogue, you could also purchase vestments, cruettes, pattons and chalices. That doesn't make one a priest though. You can clearly see why these items were made.

[Kirkwood]

That used to be the case 20 years ago or more, but most of the convents have closed their doors and there are too few nuns who do this kind of work anymore. Most nuns are now in nursing homes and few are taking their place. Yes, still a few monasteries doing this as well as making wine, but not many to assure a supply for everyone. Most of the wine actually does come from the local supermarket where the priest buys something to his personal taste. This was true even when I was an altar boy many decades ago. The wafers are mostly made by a commercial company to assure a constant supply.