For me it totally depends on when I worked out. Most nights I don't do my workout until 7pm, so I do have a snack later. If I actually get a morning workout in (which I can't remember the last time I worked out in the morning!) I usually don't have that urge to snack.
I personally think that if you look at your total calories for the day, and you still have some room for an evening snack, I think it is ok. If you have already hit your limit and you are having a bowl of icecream (mmmmmmm...that sounds really good right now!) I think then it can be detremental.