My main account has all the booster videos (Rests/Morale/Medic/Money) i usually get to watch about 5 then they disappear and come back later that day, I've done loads of surveys etc on this account before. My other account only has booster videos for money, i've never done anything to earn tokens on this account. So I guess it must have something to do with which server you're on.

I don't seem to get any on my iPhone anymore though, maybe this is down to getting so many on Facebook.