It doesn't, but nor do contract terms necessarily end the issue. I regularly hear cases on consumer affairs programs where retailers deny liability "because T&C's" only to have it pointed out that :-
- consumer law always trumps T&C's, and
- just because a contract includes a term doesn't necessarily make it enforceable.
In the case of entitlement to a refund, if contract says no, and consumer law says yes, consumer law wins.
But I wasn't really referring to entitlement but to when good customer service can make sense even if, or perhaps especially, when no legal liability exists, and that bad customer service (especially where a legal liability does exist, but is being denied) can cost customers and that doing that unnecessarily is often not a good long-strategy.
But I am certainly not suggesting that customers are always right. Quite often, they're cheeky beggars merely trying it on.