The principle is simple: to boost sales and reviews, takeout merchants offer a cashback scheme. Just give a good review as required, upload a screenshot in the backend, and you fast withdraw via WeChat or Alipay, usually getting back 70%-90% of the order. I've personally saved nearly 10,000 yuan this way!
Platforms differ in discount strength by region, so just turn on location and see which suits you. Try the few platforms listed in the doc; the more you try, the better the odds.
No fear of being scammed: these are offline shops running it, and I've used it a long time with cashback arriving every time. Each platform has support; as long as you submit the screenshot as required, it basically never fails. If one time cashback doesn't arrive, you can simply leave a bad review! On Meituan and Ele.me, reviews matter hugely to merchants, and reviews can be edited anytime, so they'll never annoy a customer.