Mostly, because controlled substances have been legally coming across the border for years (with prescriptions). This will just add AAS to the pile.
Do you think customs looks at me and goes "Why do you need this many valiums, xanax, oxycontins, percocets,and vicodin all at once?" No, I just show them the prescriptions and I'm on my way. The only time I've ever been questioned was when I brought back Viagra and all they said was "How much are those things going for these days?", LOL. (Keep in mind most of the drugs I listed were already controlled substances in the US and some of those I listed are AHEAD of ANY AAS on the controlled substance schedule list).
[617ricky, I get the feeling you didn't know Xanax, oxycontins, valiums, percocets have been controlled substances in BOTH countries for quite a while now and are routinely brought back across the border on a daily basis]
I'm sure they know in there right minds I have no need for that much of that many drugs.
All they care about is that it's been done legally and that I had the proper paperwork.
AAS will be the same way. You just won't be able to buy from the Vet anymore because he can't give you a script, you will HAVE to go to a Doctor and then a pharmacy.
Then, with a prescription in hand, you will be able to walk across the border LEGALLY and hassle-free (as long as you only try to claim an amount that can be justified as "personal use/ ninety-day supply").
I'm very surprised at the amount of you that don't understand the laws regarding controlled substances and how US laws differs from/relates to other countries' laws. I hope you guys aren't ordering steriods from a sponsor in another country without a prescription, that's illegal.