I used to think (a long time ago) that the "adoption fee" that the SPCA charged was to cover the spay/neuter costs of the animal.

But it seems that whether spay/neuter happens is rather hit or miss. Depends on the branch, the day, the age of the animal, and so on.

Giving out certificates which can be exchanged for a spay or neuter are inadequate. Now that pediatric spay/neuter is becoming more the norm, there is no excuse at all why an animal should be rehomed from the SPCA or anywhere else before it is spayed or neutered.

Not to do so, and then to scratch your head in bafflement at the "pet overpopulation crisis" is ludicrous.