Personally I have tried the peanut butter theory with my non-breeding females. Oh my it was a mess! Also two of the bigger ones decided that the smaller, now peanut butter scented, females would make a lovely snack and devoured them. Believe me, finding 4 dead $75 mice is NOT a happy occasion! For the last 5 years I have used olive oil to induce the want to breed, and have had no non-breeding mice since! I mix a small amount in with the food and change the food once a day. The mice don't get greasy and they don't eat each other =)
I also use a home mixed food source, not a store bought one as they are high in preservatives and "fillers", which, according to the companies, in most cases is paper mill products ~,~ I fed on store foods for the first 8 years and switched to home mixed for the last 7 years, they are MUCH healthier and produce many more babies =) When I get home I can do the math and post on here the ingredients I use and in what ratio I use them.. don't think anyone needs a supply for 2000 mice hehe (Yes, 2000... thats the breeding age adults, sub adults, and the weenlings, my base breeding set up it 400 breeding pairs).
Also, I find the hovel approach isn't always right for some mice. Many of mine are checked for estrous on a daily basis and are placed in a glad-ware container with a male for 4 hours, then put back with the other females. The males are NEVER housed with the females, or with each other, they are all lone housed. The females are all in one hovel. (room has 3 walls of males lone housed, and a huge 18' hovel in the middle for the females, shaped like a square-ish U... takes around 21 hours a week to clean all the lones and the hovel, them females go into a 60 gallon tank while we clean the hovel)
No, they aren't for food!!! They are bred for pets, and for shows hehe. the only ones that get eaten are the sick or deformed ones.