Perhaps IHG simply didn't view you as important a customer to them that you do?

Of course the account closures are going to be unilateral - hardly likely to be a consensus view by both parties that the account be closed

IHG did re-open your account - it is your choice if you choose to stay elsewhere. If other hotels are better placed or value for the trips being done, wouldn't make sense to use IHG. If you are putting yourself out by not using them , then is it worth it?

The whole thing seems irrelevent now - it is clear what the terms are and anyone misusing codes now has nothing to whinge about if their account is closed for doing so.