I think it takes time and patience to get bunnies used to strangers. I find the more times I have house guests the more comfortable the bunnies get.
I’ve found that it’s really helpful to have the same guest (usually one quiet person) over for a few days. When a group of people show up for just a few hours the rabbits are likely to hide. When my mom visited for a week the bunnies were able to get to know her on their own time and within a day or two they were following her around. Now, each time we have new house guests they warm up even faster. They’re definitely not comfortable with big groups though – one or two quiet, calm people seems to work best. Giving my guests a few craisins to hand out works wonders too 😉
This weekend we had two friends over for a little more than 24 hours (much of which was spent out of the house). On Sunday morning the bunnies were already running around our friends and begging for treats. A few months ago they would’ve hid the whole time, but now it takes very little time for them to start harrassing new people the same way they harrass us for treats.