If you're checking email a few times a day, you're not on vacation. You're just working remotely.
I take my computer with me everywhere I go, even on vacation. I've had conference calls in the morning and hit Disney World in the afternoon. Usually my customers don't even realize I'm out and about.
So while you could say that your not really on vacation just remote, you could look at it the other way and realize you could spend a month in Florida on vacation and still make a few bucks in the process. I've been on vacations that have paid for themselves simply by putting a little work in for half a day here and there.
It feels a lot more like vacation than work.