Ability to buy multiple kits on demand = requirement for inventory = higher overhead = higher prices. Theoretically. You can tweak the inventory need but that still increases overhead (less) while simultaneously cutting into your margins.
Any time you see "$400 value for $10/mo!" it's marketing garbage, but you really can get for $20/mo what would probably cost you $25 or a little more if you bought it on-demand.
I'm okay with that extra 5 bucks for their inventory cost if they allow me to opt out of permanently saving my details on their servers. No matter how many times I unsubscribe from their emails, they always start a new list and I'm strangely on it again.
Any time you see "$400 value for $10/mo!" it's marketing garbage, but you really can get for $20/mo what would probably cost you $25 or a little more if you bought it on-demand.