I dont feed mine on vacation. I do a water change the night before and feed them in the morning on my way out. I was gone for 11 days this summer no problems. Tomorrow I leave for 4 days.
Don't trust anyone except experienced fishkeepers. They will be fine. I once rescued a florida gar that had been abandoned and not fed for 5 months, and still recovered and lived a good life. Its quite amazing how fish can survive.