If you've ever seen a Jason Scott talk, he isn't the sort of guy who gives a shit if you DMCA him while he's sucking up all of your bandwidth archiving your content two days before your servers shut down.
https://en.wikipedia.org/wiki/Online_Copyright_Infringement_...
This is not to say that people don't send "DMCA notices" for anything and everything to anyone and everyone, but those notices are not following the law. (Also, a lawyer can always send a demand letter demanding that someone stop any behavior, but a properly-constructed DMCA notice gives the recipient an extra reason to follow it compared to a run-of-the-mill legal demand—"[a]n OSP who complies with the requirements for a given safe harbor is not liable for money damages", as Wikipedia puts it.)
Not to mention that dying websites or recent acquires are likely to be able to have the legal muster to start threatening archivists.
Obviously, there's more than just the bandwidth cost, but assuming they pay $0.02/GB for CDN traffic, we're talking about $18k. It's not nothing, but I doubt it'd change their outlook in any meaningful way.
I should add that the ArchiveTeam doesn't download everything in a day, but rather uses a distributed crawler (ArchiveTeam Warrior) run by volunteers. They rate-limit the crawling rate as needed in order not to overwhelm the site being archived.
So you should factor in the bandwidth cost for CDN traffic AND origin pulls, which if you're serving from AWS (and not using CloudFront), is $0.08/GB.
The size of your working set also influences your overall CDN bill. Storage isn't free.
The storage cost is a good point, and I don't know which CDN they use, but I expect the songs that weren't "hot" would be evicted from edge caches pretty fast, so that should be no significant increase.
To put things into perspective, an article from 2009 estimates that Spotify used 84TB of traffic per day[1], back when they had 5 million users. Soundcloud claims to have had 40 million registered users in 2013 and 175 million unique monthly listeners in 2014. These numbers aren't easy to compare, but either way I think it's safe to say that 900TB should be a small fraction of their monthly traffic, and shouldn't make a huge dent in their financials.
[1]: https://www.theguardian.com/technology/blog/2009/oct/08/spot...
Why stay with a host that bends you over a barrel for transit? Even Netflix doesn't use Amazon to deliver their data heavy content, as their pricing is pie in the sky high.
http://webcache.googleusercontent.com/search?q=cache:eCl5VSB...
In response to your concerns; I think ArchiveTeam simply doesn't care. They are very firm in their convictions, and they don't exactly listen to requests to not archive things.[0]
If you're curious, here[1] is the initial discussion that AT had. People bring up copyright concerns.
[0]:http://webcache.googleusercontent.com/search?q=cache:fmhU2zS...
[1]:http://archive.fart.website/bin/irclogger_log/archiveteam?da...
Even given that they could restrict themselves to songs marked okay to download, how much of that will be DJ mixes containing copyrighted songs?
I'm just wondering because Soundcloud actually has support to specify your copyright terms, which does not default to "everyone can download this", so it's an interesting case..
The website works now, it just says "selective content"
I'm sure SC serves up a lot of content per day, but how do you think they will react by suddenly having someone download all of their 900 TB or whatever it is in one day? How much will Archiveteam be contributing to SC's downfall by suddenly causing them a huge unexpected bill?
As someone who really wants the SC content backed up properly, I nonetheless see how this raises some interesting legal issues.