Finding site Coupons through scripting/hacking

I have a genuine question, are you able to find databases/strings that show available coupons for sites? Im looking for specifically shopify or regular website hacking tricks to find coupons. This can be used for many things. Please let me know! Thanks!

If the coupons used in the site are not very long you can try fuzzing (bruteforcing)

shopify has a generous bug bounty program. if they had such a vulnerability, i think it would have been patched long ago.
bhw isn't really a forum made to discuss security vulnerabilities of platforms. there's other places dedicated to that.
@zawali 's proposition of fuzzing is decent means to an end.