Star Trek Season 2 Episode 25

Given that they state very clearly what the Prime Directive is, how they're sworn to die before violating it, etc., they take Spock down without any head covering of any sort. Clearly their mission is going to require them to contact some people at some point, but wouldn't Spock's obvious pointed ears be a dead giveaway they're not from the planet?
Also, the landing party is wearing their usual uniforms, though it was established in previous episodes that they are able to synthesize any local clothing they require.