I can see how the DME would add to the cost to make your starters. Otherwise its getting to the point where cost for dry vs liquid is the same. Luckily for me I can buy bulk 55# bags of DME and split it with other homebrewers for pennies on the dollar. Liquid also offers more varieties and is more consistent in terms of flavor imo. I'm also still not hooked on cultivating dry yeast cakes even though brewers have had decent luck doing it. Its just a preference thing.
I pay $3.50 for US-05. 1056 is more like $6-8 depending on where I buy it. now for 10 gallons I'd need to packs of US-05 so yeah - now it's just down to the cost of the DME to make the starter. if I could actually plan to brew a couple of times in a month I could save some yeast and reuse it (I would not do this with dry yeast). so now the cost is getting closer. but then there is the time to make the starter, clean stuff up, etc. as it is now I already kind of spread my brew day out over multiple days. for instance - this is how my brew day this week is shaping up:
Tuesday Night: take out and/or clean equipment, make sure fermenters are clean, etc.
Wednesday Night: measure out grain and water
Thursday Night: Mash in, measure hops out for following day
Friday Morning: continue and finish brew day by late morning
If I were to add in making a starter I'd probably have to do that Sunday or Monday night. I don't mind it but with the family and other responsibilities it makes my life just that much easier and allows me to brew.