I remember seeing an online shop that did the whole font substitution to prevent web-scraping of their prices.. I think they even changed the substitution between elements so one couldn't just do a single pass replacement and get the original data back..

I guess nowadays it's very cheap to run a headless browser, screenshot the output, and run it through OCR.. hah, to prevent that they'd have to design their webpage as 1 full screen Captcha..