if the procedures are explained clearly and in detail from the beginning ...
if there are no hidden costs that will suprise and bite you in the wallet at some future point ...
if you like the fabrics ...
if it will be fun ...
if it fits your budget ...
then it isn't a gimmick. the shop is taking the bigger financial risk. unless they ask you to sign a contract up front, they can't be sure you will buy the finishing kit from them, so they are risking their cost of the supplies for the second through last block. they might make back that cost by attracting you to other things they have for sale, or for the finishing kit. they might not.
a program like this puts the customer in control. (well ... if it could be said that quilters have any control at all over our urge to spend on fabric and supplies. but that's another topic altogether. :lol: )
from a consumer's perspective, it sounds quite tempting. :-)