There is only so much they can do to lock it down; like all DRM, the system is inherently insecure since the client can't be trusted.
In any case, I don't see why would they care unless more than one person starts using the same UUID. If you bought an iPhone to use the service, they already got the money.
That is one way of looking at it. Consider the hardware your ticket to Siri, and as long as you don't place abnormal demand on the service, there's really no reason Apple should care.
Nothing is really free if you're getting from a large publicly traded company. They also don't use Siri to target ads towards the user such as Google and Facebook.
Excuse my direct language, I should've phrased it more clearly as a thoughtful guess. Seems like an obvious bet too.
At some point in the past they hadn't broken into the phone market, or had a music store, right? Think of it a bit like how Google created AdWords/AdSense alongside their search engine.
I got a 4s the other day and outside of the US at this point, Siri is pretty basic. Can't ask for directions. Can't find a business. Too many things get directed to a basic web search which I could've pulled up myself in the time being. Didn't take too long to realise how quickly they could monetise the experience my charging for third-party involvement, for data, etc. "When's the next SportsTeam game?" "April 1, do you need tickets?"
Apple is a company. They're there to make money. I can't see how they could not take that route if they handled it very carefully.
It's not possible to do that from the security point of view, you are the owner of the device. They can make it difficult to massively "scrape" Siri using the same device identification.
