I am not sure it is a state law anymore. I know it was a few years ago but it seems like it didn't last long due to bringing in beer at indy. I know LPS had a state law sign no carry in alcohol the past but now says no carry in alcohol. I could be wrong.
I am not an Excise Cop but In.gov says this......,
Indiana Temporary Beer / Wine Permit
A temporary permit is good for beer and wine only - not liquor. If you want to have liquor served at your event, you must have a licensed alcoholic beverage caterer. A temporary permit is valid for on premises consumption only. Carry-out sales are not permitted and persons are not allowed to bring alcoholic beverages into the temporary function.
The fee is Fifty Dollars ($50) per day. The fee must be paid by business check, money order, certified check or cashiers check. Cash will only be accepted if the application is hand-delivered to the ATC in Indianapolis.