So my MIL has planned a wonderful rehearsal dinner for us. Only problem: cash bar. Now, MIL does not have money. I told her she did not have to do a full-fledged RD and instead do something low key at her house, but she insisted on doing it at a restaurant. She barely had enough money for the food, and the wine is ridiculously expensive. The corking fee for outside wine is $10. I personally do not have a problem paying for my own alcohol but I'm afraid my guests will. Would it be rude for FI and I to buy some outside wine and pay the corking fee ourselves?