This is a good point but there are some people who still won't feel embarrased and it may be very annoying.
Every member in a team has his/her assigned work to do. I will ask the "lazy" person how s(he) is progressing regarding his/her work. I think this will embarrass him/her if s(he) has achieved nothing. If there is no improvement in his/her attitude, I'll report the problem to the team leader.