They can be skipped by the player yes.
Video ads are a entirely different beast. Instead of just popping a ad in their face video ads are often used as some sort of incentive.
For Example, lost all your lives? Play this video ad and we will give you another life. This is how Candy Crush does it. This is how I see video ads most of the time. Telling users to click then giving them some reward.
This can work amazingly well. For example one game I play right now gives me 1 ingame currency for each ad I watch. Me and my friend both sit there while watching tv and do nothing but start ads for ingame gems.
Think of how much money we are making the owner of the game!
That being said, if you would like a normal ad feel free to pick through the Prime31 plugins. I have just about every ad plugin they own as we tried them all to see what gave out the best revenue. I would be happy to make it.