Some banks report pending balance v. available balance. Other banks will clear a deposit then jerk it back to pending. I've seen it. It's not as simple as you make it sound, and people are being exploited despite keeping track of their balances.
The banks' behavior in many of these cases is dishonest.
I agree about the dishonesty. However, I can only speak from my own personal experience and I have never had an issue with this.