Consumer web traffic can be spikey, especially when running on "elastic cloud".
Handling this properly == some dropped connections until more machines spun up.
Handling this poorly == some servers crash; then if everything is load balanced, other machines get more traffic, and they crash too.
I dunno, philosophically, this idea of "sudden traffic spike => memory alloc spike => crash" seems very bad and the "correct" solution should be: machine operates at peak throughput, drops other connections.