Your example isn't truly a wash since the SPY is not the same as buying the contract being sold as you cannot fulfill the EP with the SPY. Nonetheless what you're suggesting is that you are long the commodity and short the future. This is what's called cash and carry arbitrage, and your profit will simply be the market time value of money for the perceived risk. Consider the same trade in gold. You take delivery of the contract and short the future next year... You must pay to store the gold and bear the margin between now and the date of future delivery but you will likely have some non-zero return.
This is not inherently a risk free rate, as you must be compensated for carrying unlimited risk for the shorts. However, this rate might by less than you could make in other similar investments.
A hedged portfolio doesn't seek to 100% balance a position. A hedged portfolio seeks to track the benchmark's performance with less risk than the benchmark.