Yeah, it's a tricky niche. I imagine most people who buy Classic special editions fall into a few main categories:
1) hardcore collectors who want every model ever made and who like to choose their own stuff >> people in this here forum
2) non-SAK people who are like "oh that's cute, I'll get that" - but wouldn't necessarily get more than one or two ever - however a subscription could enable the slide into addiction
kids, teenagers, arty-designy folks I imagine would be more the target audience.
For me the draw is: ho hum another day...check mailbox...surprise SAK! Agree that ~$15 per SAK is the upper limit. Here in Aus the average retail Classic is ~$20 minimum, though I understand in the US you can get new ones for like $8. Owch.