Maybe not most, but I'd gather those in the FAANG/unicorn game do - the upside is far too great to not do it. Not 1 year... but more like 1.5-2 years is probably most likely.
And we're not talking a measly $30k bump, but more like $100k. It's far more advantageous to move on than to work toward an internal promotion.
As someone in charge of hiring at my current company, having brought on 17 devs over the past year, the ones we really worry about have a bunch of 6-9 month engagements. But every 1.5 years or so, with some lesser here or there... no problem at all. More likely than not they're great at what they do.