A crowd of just 35,101 watched Saturday's 1-0 Barclays Premier League victory over Bolton at the Stadium of Light, a far cry from the days when the norm was closer to its 48,000 capacity.
Chairman Niall Quinn is well aware of the impact the prevailing financial situation has had on the city, but he fears many of the empty seats are a result of local pubs illegally showing home games on foreign television channels and has warned the days of big-money signings will be consigned to history if that continues.
Roll up: Bruce fears dwindling attendances at the Stadium of Light could hit his budget hard
Bruce admits the empty seats and the implications of that are a concern, but he has no complaints about the backing he has had from owner Ellis Short and Quinn since his arrival 18 months ago.
He said: 'There's a huge frustration because the crowds have come away, but I do believe it's an economic thing. I do think at this particular time that people are struggling and we have got to understand that.
'It's no disrespect to the team, but the numbers people - and obviously Niall is one of them - know the more people who come through the door, the more money we generate and the more we have got to spend on players.
Keep it up: Bruce is happy with his current squad
'I understand where Niall is coming from. But let's be fair, the football club over the last two and a half, three years, whatever it is, has spent a hell of a lot of money and it's not a bottomless pit.
'We can't just keep going to the owner and asking him to keep providing and providing and providing.
'I am quite happy - and I genuinely mean this - to work with the squad we have got.
'Of course, I am always on the look-out for something that can make us better, but there has to come a point - and we have maybe got to that point - where we just work with the squad we have got.
'We have got an excellent squad of players who have only been here a short period of time, and we will get on with what we have got.'
Bruce has been linked with a series of targets in recent weeks, including Manchester City's Adam Johnson and Wigan's Charles N'Zogbia, but he admits he is unlikely to dip into the January market unless an emergency arises.
He said: 'I can't see me doing anything at all in January, unless five of them fall to bits or something like that.
Wishful thinking: Bruce doubts he will spend any money in the New Year despite being linked with a move for Manchester City winger Adam Johnson
'We have made huge changes in the squad over the last couple of years - nobody has been busier, I don't think, than me.
'I think it is time I worked with the squad I have got and I am very, very happy to do that.'
Sunderland boss Bruce plots double deal for City's Johnson and Onuohall tackle Manchester United jinx head on, says Sunderland boss BruceSUNDERLAND FC