Bad Manners and Brimstone

I think saying you liked the convenience of using the site was enough of an explanation. But I would not go into the fact that you are accumulating points and that you use the points for trips with your husband. He really doesn't care about that. He's only trying to encourage you to get rid of the middle man to reduce his costs.

When we try to justify or defend or explain our actions, it's usually in hope of getting the other person to see  it from your point of view and agree with your actions. You have very valid reasons why you like to use the site instead of direct booking. But no amount of explaining is going to get him to think "of course, your right, you shouldn't save me money."