Attractiveness is correlated with trust, so people will trust you more if you are attractive than if you aren't. If people trust you more, they will give the benefit of the doubt and they will perceive things you are doing as more wholesome and less predatory.

This deals with being creepy in that your motives will seem more innocent, and/or potential partners won't care as much if they aren't entirely innocent. This deals with opsec in that 1) people will trust you more in general and find your interactions more wholesome and less blameworthy, 2) you'll have more/better options for partners so you won't need to take risks to get someone, 3) you'll be more of a catch, so your partners will be more likely to cooperate with restrictions being put on the relationship so they can have you (I've experienced this from both sides).