Option to save to true (1 bit) bw embedded image

With the relative limited storage available on mobiles, wouldn't it make sense to be able to save to the phone a PDF that uses CCITT 1 bit compression (supported by the pdf standard) for scanning pure, solid black and white line documents like receipts or all other text captures? The 'black and white' color option for Adobe Scan (and any other mobile scanner app) are really just saving a desaturated high contrast RGB image.

Going to true 1 bit would make saved PDF files much, much smaller. I have tested file size comparisons (in a desktop environment) and typically the files are at least 1/4 the size.

These true 1 bit versions display fine in all Android PDF viewers I've tried and they also send and print faster.

Is there any good technical reason why this can't work as a mobile Adobe Scan save option?