I was having lunch with my 3 y.o. daughter today, and some threatening-looking types start having lunch there also (one looked like he was on drugs). This is solely based on their appearance; they never bothered us in any way, and for all I know, they could be lovely people once you get to know them. Nevertheless, I felt a strong desire to leave, without drawing attention to us in any way (i.e. I didn't want to make it seem like I was uncomfortable with them around my daughter).
However, I know that if I would have attempted to leave prematurely, my daughter would likely have protested, which would have drawn attention to us (she was enjoying her meal, and was completely oblivious to any of my perceived threats).
Question: How can I explain to my toddler about these situations? How can I ensure that we can quickly and quietly leave in these situations?