Bizarre Behavior from a buyer

This lady just offered me on a bundle of two seperate listings giving herself 50% off. Since i already calculate my items with free shipping, it would've cost me money to allow that and make the sale fruitless so ofc i declined. I'm honestly not that hard up for money so it can sit there until someone wants to pay a fair price that we can both benefit from. Than 20mins later, she offers even LESS. LOL Naturally I immediately blocked her after declining. 5 mins later I have a friend request on Instagram FROM THEM (same name and profile pic) which I immediately blocked. Ofc i went the extra mile to find them on Facebook and successfully do the same before they could find me. My question is, has anyone experienced disturbing behavior similar to this? Who does that? Are people that hard up to get something next to nothing that it would anger them to the point of harassment? Jfc