Shocked someone would go this far

I’ve never had my photos stolen and re-watermarked or put on someone else’s facebook page (that I know of) but I’ve seen it happen to a lot of people and find it very irritating that people do it. Well this week I had something similar happen, except I think this is a step further than just stealing a photo. I had a lady come in this week and ask if 2 women (whos names I don’t remember) were working today. There are only 3 people who work in our shop and we’re all family, it is a family run business and although we’ve had lots of CVs that we’ve kept for future reference in case we ever do hire anyone we have never hired anyone outside of family the entire time we have been open. This lady had been told by these 2 women she knew that they both worked there (they don’t and I’ve never heard of them). She was then told that we’ve never hired anyone here and it’s a family run business and we asked her if she had the correct shop as there are a few others in the area. Her response was “Oh yeah it’s definitely this one because made that big cake in the window”! This has really annoyed me because the cake that is in the window is a cake that I made myself specifically for cake international at the excel this year. I have the initial photoshop mock-up that I did prior to making it as well progress shots for it. What do some people get out of lying about making something they didn’t?? I just wonder how many other people they have lied to claiming work that isn’t theirs!