coin control in clients?

[superduh]

search yielded results that didn't make sense

anyways

is there a reason that btc-qt and other? programs lack "coin control"

it appears to me that blockchain.info offers it

is there a real reason that people can't pick their "input" (using like a checkbox etc) and pick an output address (in case people want to reuse certain ones). it makes it easier for "backups" in non-deterministic clients and frankly makes sense too.
what's the official word regarding this?