my therory is they feed all night reason- last weekend i was up in scotland deer stalking and the caravan site is home to quite a few bunnys, they come out at before dark and when i woke up at 2am because the dogs were growling i had a quick shifty round the place there were about 30 on the whole place and the site isnt huge must be less than 20 vans and its in the middle of no where frezzing cold, then when i wake up at 6 for deerstalking there still out so they feed from like 6pm till at the least 6am maybe longer .
then there out on the odd occasion during the day, they just eat and eat