Ain't no such thing!
As someone that spent the first half of Easter Sunday cleaning and feeding I can attest to that.
And I see nothing wrong with making some money from something you like to do. In fact, I highly recommend it.
Here are a few things I've learned from raising corn snakes:
Don't borrow money to start your snake business, then you (and your snakes) won't be pressured to produce to pay off loans.
Do take excellant care of them, they will reward you will better quality offspring.
Know what you're getting into BEFORE you purchase your first snake, read all you can about optimum care, talk to as many people in the business as you can.
Don't scrimp on the care basics, if you have to, buy a few less snakes.
If you're serious about a certain morph, get at least a 2.3 group, better still a 3.5 group to start.
Buy the best snakes you can afford, whatever the morph/morphs you want are. Quality usually produces quality.
As with any business, don't expect to turn a profit for 2-5 years and be prepared for that. Remember - you'll also need to allow for things like food, bedding, possible vet visits and meds. so set aside some money to cover those things. In other words "Don't quit your day job"!
As far as what snakes to purchase, get what you like the most, you'll enjoy it more. I just love the bumblebees and spider albinos, so to that end I'm starting with pastels, het albinos and normals. I'll pick up a spider as soon as I have enough cash for one. If you like, say pastel pieds, work with that. If you're having fun with your snakes the money will end up to be secondary anyway.
Good luck,
Cheryl