> In fact, most of us have caustic responses to per unit pricing, often to the point of irrationality (e.g. $40 for 35 loads of laundry detergent v. $1.00 per l

> In fact, most of us have caustic responses to per unit pricing, often to the point of irrationality (e.g. $40 for 35 loads of laundry detergent v. $1.00 per load). Amazon Prime is based on the need to get shipping fees out of the way once, versus fight them over and over and over and over, even if the effective shipping cost Huh? I consider both of these to be examples of volume discounts: in exchange for committing up front to a higher number of washer loads or shipments, I get a better per-unit price. One of the biggest things that bugs be with subscriptions is they often don't provide this value, and in fact cost more than I'd normally spend. Take toothbrushes: the first service I found has a $40/yr plan. For my wife and I, I usually pick up a pack of heads for electric toothbrushes at Costco when I see them on sale and can't remember the last time I bought some - this generally works out to about every 1 to 1.5 years, costing around $10/year each. Does the cognitive burden of bit having to remember justify and extra $60/yr? For me, no.