Four of the six dismissals came post-match as a fight broke out in the tunnel following Hearts' 2-1 defeat.
The sending-offs ensured the club had no chance of avoiding a suspended £10,000 fine which had been hanging over their heads since they were docked £40,000 in the summer.
Hearts have had two men sent off since that game, though one was a second booking for timewasting, while the other was received by Ruben Palazuelos, who had been on paternity leave during the Hamilton match.
Those who did witness what happened that December day do appear to have got the message that enough is enough.
Asked if it was a watershed moment, Scotland full-back Wallace said: "It might have been.
"I don't know about the main people involved. But they know themselves that obviously it cannot happen. It was basically a wake-up call."
There have been no sending-offs since Jim Jefferies' dramatic return as manager last month but that will not stop the Hearts boss investigating whether a strict code of conduct is required at Tynecastle.
Wallace believes players are only hurting themselves and their own team if they fail to stamp out the kind of behaviour that has seen the club receive 25 red cards in the SPL in the last three seasons.
"If you're doing stupid things on match days and you're missing out on games, you could ultimately lose your place and never play for a long period of time," he said.
"It's basically their own fault if they get caught up in these situations."
Wallace scored his first goal of the season last weekend as Hearts beat Falkirk 3-2 to move back into the top six in the SPL.
The victory was the first since Jefferies' return following three successive away defeats.
The new manager knows how important it is to make the most of home advantage against Billy Reid's men tomorrow.
"Big result this weekend," he said.
"We said after three away games it was important that we win these two games.
"Hamilton won't be easy. They went to Tannadice and got a 2-0 win so that tells you how difficult a game it will be.
"Billy's always got them well-organised, they flood the middle of the park.
"If we can follow up and get a result, it'll make last week's result even better."
Wallace believes Hearts can still catch arch-rivals Hibernian and repeat last season's third-place finish in the SPL.
But his new boss was more cagey about his side's prospects of closing a 12-point gap to John Hughes' men, who have taken just one point from their last three games.
"I'm just trying to get as high as I can in the top six - that's the aim," Jefferies said.
"John Hughes has got a good side there and they've been up there consistently.
"He did say that they'd take a hit or two along the way - he said that at the weekend.
"That's what'll happen and it's how they respond from that."
Source: Team Talk