This particularly goes out to the apologists and people who say "its an mmo launch, what do you expect?"

If we, collectively, stopped making excuses for companies, and instead held them to a higher standard, no one would ever say "its an mmo launch."

Because mmo publishers would know that even on day one, their customers wouldn't put up with this mess. Have your servers and data centers in place, and stress tested for longer than 3 days before any start of early service.
This comes straight out of that entitlement mentality mixed with a good dose of ignorance. Like comma said, it would be ridiculous for them to build spend so much money to set up servers for a one-time ultra load that will unlikely last more than the first 2-3 weeks of the launch of the game. It's like buying 10 gallons of milk at the store just in case you might need them all before the next trip to the store when it's very likely you won't and they will just expire, wasting money.

People make this argument without understanding (or caring) how the business and logistics end works. It's pretty much the same with early or day-one DLC. People don't realize that there is a point that production on the launch game has to be finalized to go into printing discs and that the team may have time between that finalization and the launch to make additional content that couldn't possible be put on the disc. There's also the issue that the numbers tell them that most DLC gets bought close to launch by people who chew through the content and want me. If you wait months, less people care.

I guess a devil's advocate position would be that an MMO could potentially maintain more subs if they did account for huge numbers early on, but I really doubt that's the case in reality. The people who leave and claim downtime in the first month was an issue would've likely left anyway. Even if there is significant downtime in that first outing, there was probably enough up time for them to get a taste as see if they liked it.

They probably didn't and that's why they are leaving, or they are the type of serial MMOist who plays all the MMOs, but only for about 1 or 2 months. These were never long-term subs to be counted as a loss. So the ROI for server overkill just isn't there.