I have been craving a quarter pounder with cheese for months and haven't found a convenient excuse to nip in yet.
Sometimes, in our house, pan fried Salmon with new potatoes and salad is a treat. It's delicious food that we can't afford to eat often.
Sometimes a McDonalds is a treat, because it's unhealthy food that tastes good, so we only have it once in a while.
It's about balance, isn't it? It's about allowing yourself, occasionally, to do something that's not in your usual diet/schedule. Whatever your personal taste is, it's a treat, because it's an indulgence and not usual.
As it happens, the idea of going to an Ikea, even just for food, brings me out in a cold sweat. I hate the places. I feel disoriented and panicky pretty much the whole way round, though I'll admit, I haven't been in one for about 15 years or so (because of feeling disoriented and panicky).