No - that's the flaw in your argument.
They are not low cost. They are high cost.

The cost in BTC is above the BTC it will ever return.

Not only that, but originally when the AsicMiner USBs came out the mark up on them was at least 2000% - probably more - up to as much as 5000%

They are still priced with 1 requirement:
1) That AsicMiner will receive up front more BTC than they could get mining with them
i.e. you will lose BTC buying and mining with them

I still do not understand why so many people don't see the obvious.

More so, I do not understand why so many other people say
"It's OK to lose BTC - doing something that makes BTC"

No one who has bought an AsicMiner USB from AsicMiner or it's distributors, and mined PPS or equivalent, has got back the amount of BTC they paid for it.