Yes, but only because it would be cumbersome to bring binoculars onto a woodsball field. If the field is big enough it could help observe the other team's movements. But for accuracy purposes its not practical.
Not all scopes are big. The one that can go on my Eradicator, for example, is puny.
And it's a red dot, too! The smallest red dot I've ever seen that actually works properly! Just adjust it so it tilts all the way forward and it'll be effective for a few metres.
In short, yes, they're impractical (in the sense that they hardly help you aim at all and you'll have to aim up from where they point for the most part), but if you have a cheap gun, have some fun and make use of them.