Why did Tom want to go and eat out that evening?

Tom: Dad, what will we have for dinner?
Dad: I don’t know. Maybe fried fish, chicken soup and...
Tom: Oh, no. We’ve had such things since Mom’s gone.
Dad: I’m sorry. But that is the only thing I can cook. What do you want to have then?
Tom: I’d like to go to McDonald’s this time.
Dad: OK then. You’ll drive, will you?
Tom: No, I’m a bit tired today. You do that, please.
Dad: OK, OK. I always do things like that ... Ah, here we are.
Tom: Dad, what do you want to have? I’d like a hamburger.
Dad: Hamburger, salad, coke and apple pie. Is that all right for you, Tom?
Tom: Right, and fetch me an ice-cream, too. I’ll go and find the seats.
Dad: And I’ll get some vegetable for myself, and a coffee... Oh, I’ m afraid we’ll have to do some packing.