Late to the party, but IMO the only real way to try to avoid this is to say when issuing the invitation, “Want to go to New Restaurant with us on Friday? It’s our treat.” And even then the guy is going to offer to pay part. The response is to be breezily dismissive: Good Lord, no! Put that away. We’re treating and there’s no argument!" As others have noted, the follow-up will be an offer to get dessert or cover the tip, which offer you can take or leave, IMO.
The response of : shrug : “It’s your choice” is of course boorish. My response to that would be a warm “You’re welcome.”