Clients like it because they think the cool kids are doing it.
Clients also like gimmicky scroll effects and parallax.
How does that happen?
Apparently users like being told what they want
Design is two things: understanding people, and creating. You have to balance a pure empathy and understanding of needs and desires with uninhibited creativity. Only then will you create something that people both want and have never seen before.
http://blogs.plos.org/neurotribes/2011/10/28/what-kind-of-bu...
Those were my feelings exactly. It feels much more natural to be able to scroll the part of the page you're interested in to whatever part of the monitor is most comfortable for viewing. Also, this prevents you from quickly scrolling down to a lower section of the page.