PC manufacturers put on bloatware, and cell phone manufacturers have got into that game too - all in the name of maximising the money made.
Presumably BT will, since they're a commercial organisation, also be interested in maximising profit.
BT themselves got into this game a while ago with Phorm so it would be interesting to know what if any 'stealth trials' they're conducting to do the same here?
I just hope that they don't get expect to get 'comforting' advice from the home office if the legality of whatever it is they're doing is questioned.
If you care about privacy: avoid BT.