every place is different
I have played 23 hours in the same strip carpet joint on a four day trip spreading $25-$250 without any noticable heat. Even stayed at the same table once for over 3 hours.
I have played less than 30 minutes downtown spreading $25-$150 and been told no more blackjack.
Every place has a different tolerance level and ability to analyse your play. In the same place, some pit types know what they are doing, some do not, and some could not give a rats. Some places are nervous when they see a green chip and in other places black chips are just lost in the crowd.
Any place can also be different on different days. Big high rolling crowds brought in by perhaps a major fight can make your bets blend in without catching attention. The same place when it is slow or perhaps after they took a beating from a team could be ultra hot.
If you think you understand your surroundings, play accordingly and if you are wrong they might let you know it.