Please don't celebrate half-assing your conference talk. Doesn't matter if it's a small event or a juggernaut like #PyConUS. People pay to travel to the event, take time away from family and work, and have some expectations regarding what they will learn. Understandable!
The hallway track is great value but it isn't everything. It's your responsibility to give your public speaking engagement justice. There's many tips but at least don't prepare your slides the night before.