Mason denies Kane was saying farewell to Spurs after Brentford defeat
Kane's brilliant free-kick put Tottenham ahead after eight minutes in north London as the striker reached 30 goals in all competitions this term.
But Brentford hit back to win as Bryan Mbeumo's double and Yoane Wissa's late goal left frustrated Tottenham fans chanting for chairman Daniel Levy to be axed.
Following Tottenham's final home game of a dismal campaign, the players did a lap of honour in front of a largely empty stadium.
Kane waved to the fans who had stayed in what was interpreted as a goodbye amid growing uncertainty over his future.
After he failed to engineer a move to Manchester City in 2021, Kane, who has one year left on his contract, has been linked with Bayern Munich, Paris Saint-Germain and Manchester United.
But interim boss Mason said: "He waves at the crowd every season. I remember sitting here two years ago and you guys were convinced he was leaving, saying the same thing.
"It's the last home game of the season so he wants to show his appreciation to the support he's received and we've all received this season."
Successive defeats have damaged Tottenham's hopes of securing European football next season.
Failing to make it into Europe would be a fitting conclusion to a troubled campaign that featured Antonio Conte's departure after he labelled the players selfish and criticised the culture of a club that last won silverware in 2008.
Mason, hired after Conte's replacement Cristian Stellini was sacked, admitted it hurt to see so many fans depart before the lap of honour.
"Of course. It is understandable because of how probably the second two-thirds of the season have gone on and off the pitch but ultimately we know the fans will be there next season," he said.
"This club will keep moving forward and now is the time where we need to be stronger than ever and believe in what we're going to do, commit to it and have people that are committed to it.
"And I always say in football things can change very quickly and the energy can change quickly."
