Part of the problem is that most rescues are too demanding on their adoption requirements. They make it too hard for the average person to buy a rescue rabbit, making that average person that much more inclined to say "to heck with it!" and have that person buy from a breeder or off the internet instead. Another problem is the price tag attached. You can go out and buy a champion show rabbit from great lines for the same price most rescues ask for their rabbits - one page i looked at today? They wanted $150 for a rabbit, along with a ton of other requirements(including things such as not allowing the rabbit to be handled by children, the rabbit having an entire room dedicated to it, the owner using a specific vet, etc). When people want a rabbit, they don't want to jump through 50 burning hoops and still have to pay a ton of money besides! I find that having a waiting list, insisting people wait 3 days before committing to the rabbit and advertising well before the rabbit is available to leave(I advertise starting at 4wks, and do not allow the rabbit to leave until 8wks) weeds out the people who are impulse buying their rabbits.
If prices were dropped, or the questionaires made a little less intense, or requirements made a little more lax(if someone has a kid, the kid's going to want to pet and hold the bunny, the potential owner may not have an entire room for the rabbit but other plans can be made), there would be less of an overpopulation problem.
My solution? Well, I like it a lot better than trying to force rescue rabbits down people's throats. Really, it's quite simple, and easily done.
First, a rabbit comes into a shelter. It needs to be checked over, make sure it is healthy, no infections, abscesses, dental problems, ear mites, anything that will require medication or cause the animal pain. If the animal is not healthy, it should be chemically euthanized and incinerated.
Rabbits that pass the health test would be evaluated for personality. Rabbits that are easy going, inclined to do well in a home, that are litter trained, etc. Those would go into a holding facility where they can meet and greet the public. Rabbits that do not pass the personality test, but are healthy, would be placed in a different facility, deemed unadoptable. Both groups would receive healthy pellets, fresh hay, clean water, and absolutely no vaccinations, worming, treatment of any sort.
All rabbits who make it into the holding facilities would be kept for 30 days. Those that are deemed adoptable would then have 30 days to be placed into an actual home. Not a rescue group or a foster home, they would need to go into an actual, forever home. Prices could be on a sliding scale, the older or larger the rabbit, the less expensive it is, or it could be one flat fee. Doesn't matter, as long as the price is reasonable, and not outrageous. Alternative things could be considered as well - pay x price for your rabbit, and our vets will perform a desexing operation before it leaves and provide you with the medications for follow up. Something like that. I understand that when you are selling used goods, you generally have to have "value added" prices.
Breeders would also be considered to buy these rabbits - since the rabbits won't be desexed, they would have a use to breeders of all sorts, especially if they are purebred, or come from an abuse seizure. Why discriminate? These rabbits are considered unwanted, so why would a breeder not be considered - the rabbit would be wanted to them!
Now, for the rabbits who don't sell within 30 days, or who are deemed unadoptable, they have a chance to become wanted again. Why waste their lives by chemically euthanizing them and discarding the bodies when you can easily butcher them and give them a purpose in life! Rabbit meat is considered a high class meat, it is expensive to buy and hard to find in grocery stores. Which is totally stupid because it is an easily produced meat, with very low global impact from feeding or growing it.
You butcher the unwanted rabbits. Humanely butcher them, and use every part of their bodies. Meat donated to soup kitchens or food banks, head and offal sold to raw feeders for their dogs, feet preserved and sold as trinkets, pelts either sold raw or sold tanned. All the money put back into the shelter system, to help offset the costs of evaluating and feeding rabbits.
It wouldn't take long for unwanted rabbits to be a thing of the past.