I believe we can solve the food issues without compromising the existing system with two fairly simple changes:
One, allow lords to create (but not accept) trade postings while away. This way they do not have to stay at home, but to complete a trade it needs either someone staying at home or a trader. The whole realm could be away on a war with a few traders back home brokering all the trade deals the lords post.
Two, allow lords to post future trades. In addition to an end date, you can also give them a start date. For simplicity, one to four weeks in the future. That way, you can deal with food once a month and be done with it.
This would allow for the usual recipe of making things less hassle but if you invest the time to micro-manage, there's a small advantage in it. And it would still require intentional actions instead of automation and "not my problem".