As a pet sitter, and animal rescue volunteer, and cat owner (I keep mine inside for their own safety), I have heard a great many irate homeowners complain about cat feces ruining their gardens.
Whenever possible, I have asked the complainants to show me the affected areas to see if I can offer any suggestions for eliminating the issues. In every single case, the homeowner has been incorrectly attributing raccoon feces to a neighbourhood pet.
Cats are fastidious creatures. They are averse to digging and squatting too close to other waste products; a clean, indoor litter box wins every time. Raccoons will return to the same spots over and over again. Their poop is similar in size and consistency to a small dog or cat but is almost never buried unless it is inadvertently disturbed by another deposit. It is, indeed, very smelly. They are especially fond of areas close to foundations, gardens, food sources (grape vines, fruit trees), the bases of trees that they climb, under stairs and decks and so on. They will also mark their territories with urine, sometimes leaving little pools of it on steps and door sills.
Cats get blamed because they are visible in the daytime but most Saanich neighbourhoods are teeming with raccoons who may be active both day and night. Cats will sometimes investigate raccoon feces and even try to bury it because it offends them, too, hence the insistence of some homeowners that the cat is to blame. A viewing of the feces by someone with some knowledge of scatology can easily settle any conformational bias.
As for the songbird crisis, it is important to remember that a great many animals besides cats, as well as many other birds, also contribute to that oft-quoted government ‘estimate’ but it is humans who raze forested areas, prettify the trees and shrubs in our own backyards, and ‘develop’ buildings and roads that are the root cause of their greater exposure to all life-threatening hazards.