I think the reasoning goes something like this..."we know that the official show contractor would charge you $25-$35 to receive a package on the show floor...we know you are trying to beat the system by having things sent to the hotel to bypass those charges...so why don't we charge you for the priviledge..."

Unfortunately, that thinking is very shortsighted...and the hotels that spring those types of charges on me are hotels I don't stay at in the future.