Well yeah, but those frozen pizzas ain't advertised as being already-prepared, either. You can't usually just thaw a frozen pizza and expect it to be edible. They also tend to be made pretty differently than how they're made at a pizzeria.

The market for frozen food is already well served.

If you want food from a particular restaurant, then you probably want it in the way that restaurant prepares it.

I have a favorite pizza place, from the town I grew up in. But there's no particular reason to believe their their pizzas will handle being frozen and then cooked at my place better than, say, DiGiorno -- if anything DiGiorno should have a pretty big advantage, they specifically designed their food to come from frozen and be warmed in a normal oven.

The only use I can think of for this is specifically for people who are feeling nostalgic about the leftovers they ate in college...