Very few are considerate of others when they are not paying for the food..Yes.The best way to mind your manners are by being considerate of the other person who is spending.
Check what the host is ordering, order the same or order something up to that price.
If the host indicates you to order whatever you like, you can order anything that is priced average.
Dont order expensive items from the menu unless the host specifically suggests something on the menu for you.
Do not order multiples items from the menu just because you want to and you dont have to spend. Be thoughtful.