I do, especially on the train so the stupid business men that hide behind their newspapers when they notice someone getting on the train that might need their seat.
unfortunately it is usually someone old or a woman that gets up for me!!!
Once i had someone in her 70's get up for me when i was heavily pregnant, i couldnt take her seat, the two young guys next to her just buried their heads in their newspapers even more and i think i burnt a layer of skin off rubbing my belly that day!!!