Why would they make something like this!

I was late for four weeks and decided to take a test, I stayed at my friend's place so I borrowed one from her. It came out with two lines and I swear I almost had a heart attack. Then she told me it was a fake test she bought to prank her bf on April fools--no matterwho pees on it, it'll be positive 🙄🙄🙄
Just... why?!
What if some awful people uses it to steal another woman's man by telling her that she got pregnant 🙄