Adebayor told reporters: "The most frustrating thing of the afternoon is that we weren't rewarded for our performance.
"If you play badly and draw, then it is quite good - as I am sure the Sunderland players will tell you. Their manager won't be able to believe they came away with a point.
"We've got to finish teams off when we've got them on the ropes. We didn't do that today. It's difficult to take after dominating. We're very disappointed because we should have won the game, Sunderland will be happy playing like that and taking a point."
Tottenham are currently sixth in the Premier League after four matches of the season.