Also American, and I would find that frustrating if you were a co-worker who was traveling with me. Over the years, I've learned that I can appease most of my early colleagues by suggesting a 6 pm dinner, leaving the hotel at 5:45ish. It's a fair compromise for the early eaters like you and not so early for the rest of us that we're still full from lunch. My other trick is to suggest meet in the hotel bar for a drink before leaving for dinner...when you have a group that always lasts longer than people expect.

Interestingly, for many years I would have been horrified by a pre-7 pm dinner time. It was common when I was commuting to an office that I wouldn't get home until after 7 pm and my body adjusted. Now I've settled into a "between 6 and 7 is fine" schedule.