Impact of OS/VC/IS on battery life

I have to say that so far I've been super impressed with the battery life of the LP-E6 batteries for my 7D. With the battery grip I can shoot all day and not even think about battery. Well, last night I was shooting a wedding and using my brand spankin' new Sigma 17-50 f/2.8 OS. Loved the lens! BUT...It did seem that the OS sucked battery life like crazy. Now I have VC on my Tamron zoom that doesn't seem to drain battery life like this. My question is whether this is considered normal or not. Anyone have any thoughts or experiences? Thanks.

Not normal for a Canon brand lens--unsure of a third party.

I can shoot all day tournaments with my big 300--run the IS hours on end-- and never need to replace the batteries if the weather is decent.

Temps around freezing is another story

Seems like battery life is down since I picked up 55-250. Maybe 33%. was it cold out, did you use a the on camera flash?

Battery life also goes down fast when I shoot in liveview.

Can get through 6 batteries in a day with a 7d gripped.