Dramas? Well, you would be breaking the rules of IHG Rewards Club. So your friends need to behave as if you are physically there or arriving later. It does start looking suspicious if a room is booked in your name, but somebody else checks in (as second guest), spends the night with a third person who isn't you, pays with their own credit card, etc. You might easily find yourself with zero points or night credit, or even an account closure if you've ever done anything like abuse promo codes.

Given IHG don't really have in-hotel benefits worth noting, you might be a better friend by suggesting your friends sign up for the Accelerate promo in their own name(s) - 2 stays = 1 free night anywhere, 2 more stays = another free night... If it's a couple they could alternate one night in person A's name, second night in person B's name. Much more legit and much more lucrative...