I also have issues with teleporting supplies to your camp (why? how!?)
In my second playthough I exploited the crap out of this. I picked up every single oil and gunpowder barrel I found and sent them to the camp so that when the grove siege happened, I retrieved all of them and scattered them around the entire area. It turned a 20-minute fight in my first playthrough into a 3-minute fight.
Of course. The obvious solution is to just have most/all companion dialogue available when traveling. I don't know of many companion scenes where the camp setting is necessary anyway. The only ones that come to mind are
Raphael making his offer and Astarion trying to feed on you.
The long rest limit is just my solution for game balance, which IMO is more vital than missing some dialogue is.