One trick for avoiding this is to use artifacts in the PoC that no self-respecting developer would ever allow in production. I use html tables in PoCs because front-end devs hate them - with old-school properties like cellpadding that I know will get replaced.

I also name everything DEMO__ so at least they'll have to go through the exercise or renaming it. Although I've had cases where they don't even do that lol. But at least then you know who's totally worthless.