You are into 'computer speak' here. Real people see 3, 03, 003, 0003 as the same thing, a simple 'three'. Computers, (which is essentially what DCC is) unless programmed to ignore leading zeros, don't. They see the leading zeros as a 'something', hence why 'simple systems' see 0003 as different from a plain 3.
Just part of life's rich texture, which does pong a bit at times
regards
John