My hunch is that Traveler card was intended for less frequent IHG users who don't want to pay annual fee and to earn points occasionally. In the end it ended up being additional venue for reward chasers who already have at least 1 IHG card or even both (Select and Premier) getting more free points, especially when they had SUB of 100K with the possibility of PC to IHG Premier later.

This was actually my plan but given how fast IHG points have devalued I switched to other hotel chains (as far as credit cards) instead.