YES ... sort of ... maybe. Unless a recent edition changed it the National Fuel Gas Code does not prohibit galvanized piping in gas installations. Yes, there is a concern about zinc flaking off, but no more of a concern than copper sulphite from reactions between impurities in the fuel and copper in the system. This is why you need a properly installed sediment trap (aka drip leg) before each appliance. 
And remember, this is NOT the way to install it:
 (sediment trap WRONG.jpg)
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 sediment trap WRONG.jpg (44KB - 870 downloads)
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Propane and galvanized pipe
