I very much doubt that AM can produce a USB miner for 50 cents.
Here's one attempt to go through the components on the USB Block Erupter and looking up the part codes on Digikey:
Top left: NXP Semiconductor 74HC574 (octal D-type flip-flop), about 0.12 USD
Top middle: Atmel ATTiny2313 (8 bit microcontroller), about 0.72 USD
Top right: Silicon Laboratories CP2102 (USB to UART interface), about 2.30 USD
Bottom right: Alpha & Omega Semiconductor AOZ1021 (3A synchronous buck regulator), about 0.50 USD
So that's $3.64 for the non-ASIC ICs only. Add to that: Block Erupter chip, PCB, heatsink, USB connector. Not sure what these parts cost, but I'd say they add up to at least an additional $1.36, which brings up the total marginal cost to $5, or $15/GH - ie. 10 times the $1.5/GH figure.
That's a 60% profit margin.
even at 60% profit margin, that's pretty good, considering how many they sold at .5 btc or better.
Even at 60% profit margin, it makes no sense to mine with this hardware if you have sellers (which I assume they do, as they keep selling out).