My very first day I was amazed how much access I had at will.

Another branch where you might expect security awareness is anti virus companies. I'm a pentester and in smallish companies everyone knows everyone, but nobody knows me, yet most days I can tailgate into the office without question. This morning a lady asked suspiciously "are you looking for someone?" and I just replied that I know where to go, thanks. I walked on and she didn't pursue. Free rein.

I don't have to mention any specific company, this happens everywhere. Helpful, trusting that everything will be alright, clicking links... Vulnerabilities help but they are optional.