Shock/Strut Replacement Affecting Fuel Efficiency, trip mil

I have a 2008 Honda Civic Si Coupe and just last week, I had the front shocks/struts replaced under warranty due to this noise in the steering wheel.  As soon as I got the car back, my last two tanks of gas, my fuel efficiency dropped drastically.  Since my car is equipped with a digital gas meter, over the past 3 years of ownership, it always drops a bar of gas around the same mileage (I reset the Trip Mileage every tank).  The weather, my driving habit and tire pressure all remain the same before and after the warranty work.  I am 100% sure of that.

What can I check or could've went wrong with the front shocks/struts replacement that can affect fuel efficiency??

Thanks so much for your help!  

Answer
    The only thing that I can think of is that they might have accidentally disconnected something.  Or had to disconnect to do the job and forgot to hook it back up.  Take it back and bitch them out.  And don't let them try to convince you that whatever it is isn't related to the work they did.  You might have to get in their faces, but they have to take care of it.  If this is the dealer we're talking about, you can complain to Honda if they don't make good.  Honda takes a dim view of their dealers screwing over their customers.
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