Originally Posted by Chewy
Maybe confused to the point of asking someone or googling who that guy was. Kind of like the Thanos scene after the Avengers' credits.
Which seems like the point - it helps to drive interest in the characters' future appearances without being overwhelming or off-putting to those not in the know
^this. of course having the camera randomly focus on non other than Jeremy Renner will lead to questions.
But the cameo itself was very well crafted into the story. He had a purpose in that sce. Almost every other agent of SHIELD could have done the same thing he did (which would have happend if Whedon would've said 'no' to Renner as Hawkeye), but instead they chose Clint to appear. A very wise move to get the attention of casual movie goers and make them interested in that character.