I'm not sure if you understand what I mean by pricing tiers. I have no objection to people paying more in order to get more -- by pricing tiers I mean things like "plan A costs $5/month and lets you store up to 20GB; plan B costs $10/month and lets you store up to 40GB" because with a pricing model like that the 20,000,000,001st byte ends up costing $10/month, which is plainly absurd.
I also find price discrimination inherently distasteful -- but even if I didn't, I'm not sure how it would be possible for tarsnap without adding a lot of extra complication.
I'll take your word for it that price discrimination would be difficult for tarsnap, but I don't think there's anything particularly distasteful about it as long as you're not sneaky about it (i.e. Amazon showing different prices to different people, who then figure it out and get irritated).
I keep hauling out the 'Information Rules' book because it's so good... I just picked it up and looked, and they do cover price discrimination some. There are plenty of examples where it's not really unfair, mostly where people self-select.
For instance, coupons are a way of getting people to buy something they may not have otherwise bought, with the thinking that those who have time to sit around clipping them out are a group of people with less money than those who simply don't care and go to the store and buy stuff without looking at the price much.
Student and senior discounts are another one that doesn't strike most people as 'unfair'.
