Still disagree. The shop/stealing analogy was your's and needs to be applied consistently to have any validity. The fact that the shopkeeper is virtual in IHG's case does not mean the shopkeeper is not there. The teenager taking the coffee is very different from the teenager being handed the coffee by those in control of the coffee. IHG has possession and control of the points and IHG gives them out - it is the virtual shopkeeper. The correct analogy is not a teenager actively taking a coffee, it is a teenager asking for a free coffee and the shopkeeper handing it to him.

In fact, an even more rigid analogy would be a sign in the window saying Free Coffee for Those Eligible. Someone goes in and asks for a free coffee is given it and then afterwards charged with theft because the shopkeeper mistakenly gave it to an ineligible customer even though the customer had no way of knowing the eligibility criteria.
The customer has no idea if they are eligible or not. Sometimes when you register for IHG promos you get a rejection saying you are ineligible. Is it not then reasonable in the absence of being provided eligibility criteria to rely on the system to decide given that it clearly has that capability.
Is there actually anything in the Ts+Cs that says you can't attempt to register for promos that you have not been targeted for. The great majority of promos that IHG runs I get no personal invitation to participate in - I have no idea if they are targeted/restricted or not. To expect customers to discern which offers are general and open to all and which are not is unreasonable.