So if the server already knows, it'll instantly send me its response.

How else would the server know where to send the data?

The perceptive server knows this and takes the appropriate therapeutic measures.

When meals are delivered, some servers know where to place them, others have to ask.

Unlike clients the server knows the exact current game state, and as such prediction is unnecessary.

I make sure the servers know to bring their orders quickly so they are not tempted to walk around.

You ask for this page, and then that's the last the server knows about you.

When eating out, let your server know you have special dietary needs.

That server knows you because you've established an account and some sort of identity with it.

Problem is, the server has cached poisoned information and doesn't know it.