I tell people if they ask, but my best friend (who is dead scared of snakes) just bought her 3rd dog, and God knows it cost way more than my snakes, so she totally understands the cost of pets, even if she can't understand why I'd want to even own snakes in the first place. Fortunately we are extremely tolerant of each other's quirks.

Certain people I don't even tell when I get a new snake (like the new one I got today). It doesn't concern them, and although I may be excited and eager to tell people, there are people who's reactions I'm just not interested in. My mom is one of those people LOL. She does love reptiles, but her "you're crazy" look when I even bought my second snake was enough for me to decide to not tell her anymore.