The thinking is probably that if usage spikes and some people can't get access to the game and they know that this is because of spiking usage, then this just b

The thinking is probably that if usage spikes and some people can't get access to the game and they know that this is because of spiking usage, then this just builds buzz and demand -- like hip restaurants with visible queues. So in this case the business demand on the engineers was presumably to make sure that 10% of users get good service during the spike while the others are gracefully shown a "Sorry we are too busy right now " message. Whether or not this is evil depends on the pricing model and other factors that determine whether those bounced user had a reasonable expectation of service.