No return spring in SRAM Rival 1 brake lever?

By design:

https://road.cc/content/review/31892-sram-s900-singlespeed-carbon-brake-lever

" Feel at the lever would make Goldilocks proud, not too baggy, nor too snappy, in fact just right, but there's no return spring which might be a problem for those that prefer gritty cables."

https://www.amazon.com/SRAM-Rival1-Pair-Brake-Lever/dp/B017EET2TE

"I like these levers, please note, they do not have a return spring... thus the 4 stars. Also, people are telling me these are the same as the 500's but just with fancy graphics. But I like fancy graphics, so that's cool. But really Sram, why not add a return spring??"

https://www.lfgss.com/conversations/337133/

https://www.retro-gression.com/products/sram-s500-brake-levers

"The S500 features a composite body with adjustable-reach aluminum levers.

These don't have a return spring so you'll need to get creative if you only run a front brake and don't want the unused lever rattling around. You can do it!"