i was worried last year when DD and DSIL went to Alaska...
DD is an American, but DSIL isn't.
He has a multiple entry tourist visa to the US (where we live isn't an ESTA country yet - supposedly next year it will join the list).
Anyway, i was worried they'd have a problem going in and out of the US - they entered the US in New York, but then a week later, exited the US in Alaska when they boarded a one way southbound alaskan cruise headed for Vancouver Canada. But after debarking in Canada, they re-entered the US the very next morning (by train from Vancouver to Seattle).
I was worried that the entry/exit/entry in such a short period of time might be a problem for him.
So i wrote to the US embassy to ask. They said no problem. And it wasn't.
If it wasn't a problem for someone on a tourist visa, it shouldn't be a problem for an ESTA visitor.