Ronaldo returned to the starting eleven and scored against Sheriff in the Europa League on Thursday when Manchester United recorded a 3-0 victory at Old Trafford.
The 37-year-old walked away before the end of Manchester United's 2-0 win over Spurs last week.
Manchester United manager Erik Ten Hag responded by dropping the five-time Ballon D'or winner from his squad for Saturday's 1-1 draw against Chelsea before he returned to Chelsea this week.
United legends Rio Ferdinand and Roy Keane have already defended Ronaldo's actions and now Scholes has doubled down on his former colleagues' assertions.
"The longer the game goes on, the more upset you get, the red mist comes over you," Scholes told BT Sport.
"You're not thinking properly. For him [Ten Hag] to ask him to come on with two minutes to go, he will think: 'Is he taking the mickey out of me?'
"He thinks he should be playing every single game, and some players just can't accept being left out. The longer that game went on, the more and more furious he got.
"I think the manager has to show a bit of common sense. You're looking back at an experienced player, and you're asking them to come on in a game that's won.
"I've heard a lot of people say Sir Alex would have gone crazy or mad, but I don't think he would have done that. With two minutes to go, you bring a young kid on or give someone his debut.
"I think it's disrespectful towards Cristiano, but it's difficult to say it's disrespectful because it's the manager's job, and he's got every right to ask him to come on.
"It's clear Cristiano isn't in his plans. He doesn't see him as part of his team in the big games in the league, the big European games later in the competition, he sees him more as a substitute."