We have a colleague who is always instigating work socialising and organising nights out. Prob is she never wants to pay for anything. She never ever buys a drink. She always asks me and my colleagues to get the bogof drinks and she will get the next ones but she never does. She has blagged lunches off colleagues by forgetting her purse app and never paying back. We went out yest and my colleague said she would get the first drink but she needed to get the next ones. She never did. It was awkward as she just sat there with empty glasses. A couple of times she has been on lunch and said she needed a sandwich but forgotten her purse. We went in the sandwich shop once on her request and I'd already eaten a sandwich from home as trying to save money. She looked in her purse she only had some pound coins which she is collecting app. She then proceeded to ask me to pay for her sandwich as she can't spend her coins as collecting. She's asking me and a colleague to come on a few nights out with work in the next few months and trying to convince us to come for a break away. I don't know how to deal with her politely as she won't pay for anything! It's really starting to piss me off. Aibu?