That analogy had also occurred to me, Nailit.
It's actually rather a strange feeling (psychologically, rather than physically) when you're told, "Yes, you can take a bus into town but make sure don't sit anywhere near to young children or pregnant women".
I was a bit worried that a pregnant woman might sit near to me and I'd have to say, "Excuse me madam. I've got to find another seat, as I'm not allowed to sit next to you". She'd probably have thought that I'd got some sort of restraining order!
;-)