I do think 'open' banding at 1800+ is too low. The banding might be better restricted at 1800-1999 to avoid 2000+ players 'spoiling' the fun. On the other hand, I've only seen one 2000+ banded Octet in my short time here; hard work but a very enjoyable contest too - for me anyway, as you can see Tournament 5916
Do 2000+ players like to enter 1800+ tournaments? I can only speak for myself of course, and my answer is: not really. It's generally best to allow players of roughly equal strength to enjoy themselves. Few strong players enjoy beating significantly weaker players - although there are obvious exceptions.
One further point: those of us 'destined' to be 2000+ do not start out at that level. Early on, I did find 1800+ and similar banded tournaments a good way of quickly reaching my 'natural' playing level - of course, I wasn't yet rated 2000+. But now I'd not go back and enter 1800+ tournaments unless they were 'themed' or of special interest