Sometimes I think people are embarrassed to be looking for a bargain on anything, and others might feel that the care animals receive at a low-cost clinic is not as good as at their vet's clinic. Thinking about it, though, doesn't it make sense to go to a specialist when you need medical care.....and who is more a specialist at spay or neuter operations than a vet who ONLY does that type of surgery. And, the prices are much lower than at a 'retail vet.' For cats the cost to spay is around $50 and to neuter around $40, at our local clinics. That is less than half of the usual spay or neuter at a full-service vet.
If you have a clinic in or near your town, make sure they are in the listing at SpayUSA.org, and consider putting up a billboard to let your community know about available referral services.
http://spayusa.org/
The billboard art is FREE to folks that would like to display it in their communities, with a small handling fee. (I bet you could get an outdoor advertising company to discount or donate the rental for a month or two!) Getting the word out is definitely a challenge. My friends in animal rescue and I all know about the various spay/neuter options, but many people that I talk with have no idea the clinics are available and affordable. Spread the word!