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At various times during the trilogy people are trying to find the Batman’s real identity.
Knowing the costs of Batman’s toys wouldn’t someone even suspect one of Gotham’s young rich men?
And the following points:
- the Army knew of the Tumbler, or at the very least people who work for Wayne Enterprises would recognise the equipment
- Coleman Reese
- Bruce Wayne re-appears just as Batman does
- "the Bat" is not a cheap bit of kit, not many people could afford it
- when Harvey Dent asks to take the Batman into custody, no-one notices Bruce stepping forward