20 dollar diff I'd probably go to a breeder too.

But I never have so I understand your delima. It's so much simple to drive to your local pet store and pick up a baby bp, vs. worrying about shipping and live arrivals ect.

You have to balance the pros and cons of the situations.

Breeder
Pros
Guaranteed health
" " sex
" " morph
" " age
" " feeding record
professional help
knowledgeable help

Cons
Shipping cost
Must plan to be home for package
Can't see snake in person till after purchase
Hassle of ordering
Waiting

Petsmart (any petstore)
Pros
Ease of purchase
Take home same day
Can physically see snake and shop environment
Can have a 'love at first site' moment before buying.

Cons
Unknown sex
" " health
" " morph
" " age
no feeding record before the store got the snake
Don't know the breeder/supplier
Un-knowledgeable staff
Risky/vague return policy


Basically with a breeder you know exactly what you're getting and so does the breeder/seller.
With a petstore you can never believe them if they say the snake if female (how do they know? I had a petstore staff member tell me the snake was male cause it was the "biggest one!" once) The people who work there could have chosen to work at McDonalds instead. They do not hire animal experts.
Occasionally you meet a petstore employee who knows his stuff. But more often than not they know less than you do, especially when it comes to chain stores like petco and petsmart.

I'm guilty of buying a snake from petsmart (this was before I knew about breeders and shipping)... but I still think I would have gone with the petstore because I was excited, it was my first snake, and I wanted it 'right now'
I may never buy a snake from a petstore again. But I may never buy from a breeder either, all my snakes after my first have been rescues/craigslist finds (talk about not knowing the health of the animal. lol)

But anyway, sorry for the uber long post. And hopefully that helps.