It's also possible they care more about some hours than others -- everyone needs some downtime, so hiring a professional knitter it wouldn't help at all. Wherea

It's also possible they care more about some hours than others -- everyone needs some downtime, so hiring a professional knitter it wouldn't help at all. Whereas saving hours on the crunch day when you're chasing a deal is worth a lot more. That said I think there's also something in the social acceptability of services being higher than that for servants.