[quote]if I get a Bengal cat, am I indirectly ensuring that a humane society cat gets euthanized?
No. You're directly ensuring that.
If you go to a shelter and adopt Fluffy, Fluffy gets a home.
If you go to a breeder for a designer pet, you don't adopt Fluffy.
That doesn't necessarily mean Fluffy won't get a home. Perhaps a less shallow person who chooses not to support the unethical pet-breeding industry will adopt Fluffy.
But that less shallow person who chooses not to support the unethical pet-breeding industry would have probably gone home with a pet anyway, say, Snowball. But now the lspwcntstupbi is taking Fluffy, who would've been your choice, so Snowball stays behind. And when it comes time to euthenize the picked-over animals to make room for the endless stream of new strays and castoffs, Snowball gets gassed.
So yes, every designer animal you order from a breeder in lieu of a shelter pet directly causes another, unwanted animal to be put to death.
This is simple math, which anyone over 4 could grasp, if they weren't internally trying to persuade themselves that purchasing a designer pet from a breeder when shelters literally can't give away unwanted animals fast enough doesn't make them a horrible, selfish person.
Enjoy your Bengal! If you're truly devoid of any shred of humanity, you probably won't see poor, dead Snowball staring back when you look into her eyes. Just shower her with all the affection and comforts she's earned by being an expensive, custom-bred, genetic anomaly that makes the perfect accessory, too. After all, you're an "animal lover".