I mean it's not like cast albums are a super profitable venture anyway as you say. The demographic for them is in a large part very much in favor of physical copies as well, be it CD or vinyl.
I don't imagine you've ever purchased the format but they actually are a decent bit more expensive to purchase than a CD, which is already more expensive than a digital download.
I'd be interested to see the breakdown of how much a CD vs. an LP cost to produce.
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