I do sometimes overindulge at UL lounge at CMB or CX lounge at HKG. UL because of the food they serve, it's something that is close to my heart and I love Sri Lankan fare. HKG because they make a mean lentil curry & chickpea korma - both are so good with roti. So those are the 2 places where I don't mind overindulging.
Edit: Worth mentioning the EK F/J lounge (regardless of the departure port) - they usually seem to serve spicy middle eastern/Indian fare, which I quite like .. so, I do overindulge if in EK lounges
Re: AU lounges - not so much, primarily because there is not many vego options ... last week at CBR QF J, the only vego option was the cold vermicelli, carrot & tofu salad. Even the soup had meat in it, so had to help myself to a portion of the vego meal & a dessert. Even VA lounge has only a salad option as vego. Sometimes they do a red curry, but I can't have it because it has fish sauce in it .. so most times it's the bread roll or salad or dessert for me .. #NotAppetising
Edit: Unless, of course, some vego is served at the Spice Bar in MEL J, then I do overindulge