What is actually happening here isn't the problem. What I see as the problem is that the arrangement isn't working for you. If it's not working for you you should do something to fix it. If you need him to take you out more often to wine and dine you let him know that. Be very clear as to what your needs are. Give him the chance to meet those needs. If it turns out that he can't meet your needs are you able to go elsewhere to have those needs met?
Personally I wouldn't want to be with someone who was just in it for the sex with other women. I like to know that the people I'm with truly care about and love the others who they are with. If you're happy with it though by all means carry on. One of the good things about open relationships/poly is that there is no one "right" way to do things.
I was wondering if he's laying it out to these other women that he's only in it for sex with them. It seems a little unfair to these other women if they are being led on under the pretence of a dating/love relationship if the sole goal is just to get into their pants. Everyone involved has the right to know what the situation and expectations are.
Everything will be ok in the end. If it's not ok it's not the end.