Are audio/video conferencing services really needed?

[any ANONYMOUS forum user]

Are audio/video conferencing services really needed? Don't phones/skype/google talk/jabber/MSN do the same?

One can set up a videoconference via Skype, google, jabber, msn or via a $50 downloadable software.

Why would companies pay for audio/video conferencing services?
Thanks

Services like WebEx are really useful, because they allow you to have a conference with 1000 persons. Besides many such services have very useful feature allowing to send invitations to conferences, so people can schedule them. Many of them allow you to share your screen, record an online meeting. There are some other useful features, every conferencing service provides a different set of features.

Such services compliment Skype, Google Talk, Jabber, MSN.