What is so special about Franking Machines ?

[JustaQuestion]

I was just looking at the royal mail website to see the cost increase and I noticed they suggested Franking Machines to medium/high volume customers.
Given the changes over the past few years to allow purchasing of online postage as well as click and drop, why is postage cheaper with Franking Machines?
Looking at the some of the small examples they just look like printers with scales attached, that "will automatically update with Royal Mail’s best value franking tariff, saving you more against stamps than traditional franking."

It seems to me that I can now do exactly what a franking machine can do using the web frontend, but without the cheaper postage rates?

[N|M]

If i was told right, franking machines are cheaper as there is a different tariff used to that of stamps, plus it weighs the item and correctly prices it up,

Not sure on the amount of savings to be made though.

[leamphil]

I believe companies with franking machines have to have an account with Royal Mail and pay in advance - the machine will only frank up to the amount in the account.

So RM is getting the money earlier - is that the reason it's cheaper ?

[wallan]

No Stamps to be Cancelled , items have to be Segragated into Red ( 1st ) & Green (2nd ) Class Pouches , Pouches should be Posted at a Sub Office / Do Eng Office or Posted in a Business Box

[SpacePhoenix]

No Stamps to be Cancelled , items have to be Segragated into Red ( 1st ) & Green (2nd ) Class Pouches , Pouches should be Posted at a Sub Office / Do Eng Office or Posted in a Business Box

There's also white and yellow pouches. The white ones are for any airmail or surface mail (stuff going abroad), don't remember what the yellow ones are meant to be for