A friend of mine took 7 years to conceive, and had gone through so much stress with trying, ivf, believing she was infertile, and worrying about miscarriage that the stress of labour was something she just didn't want to think about. She seemed to be very happy with her C-section and it made her pregnancy less stressful for her. She went on to have twins (naturally conceived), also by C-section, but went into labour initially so at least she got to feel what it was like - and I think she was pretty happy not to go through it!
Not for everyone, and not for me, but for some people I think they feel safer with CS.