I'm going to put in my 2 weeks notice while on vacation
Why not give your notice after the vacation?
Because I won't enjoy my vacation knowing I will be working there after.
Nobody wants to work after a vacation but it is what we do. It is not good for your co-workers and your boss to deal with your unexpected absence.
So what? I'm a human being, I can do whatever I want. I have thoughts on my mind, and I'm sure others do too.
But you are burning that bridge. What happens if you can't find a new job or your new work ain't doing it for you? Do it properly and you'll have a job to come back to.