Andres Iniesta's extra-time goal handed Spain a first World Cup triumph, with the winning strike coming seven minutes after Heitinga was given his marching orders for a second bookable offence.
In all, 14 yellow cards were issued - a record number for a World Cup final - and Kuyt believes that Webb was not favourable to his side at Soccer City.
"We are angry because we were so close. The referee was slightly more for them than for us. That ultimately cost us the cup."
Netherlands captain Giovani van Bronckhorst will now retire from professional football and while the left back did not want to end on a downbeat note, he is proud of his team's effort throughout the tournament.
"We were so close to being world champions, but it didn't work out that way," Van Bronckhorst said. "It is very disappointing.
"I am very proud of the team and everything we have achieved. We came far, we gave everything today."