Seems quite simple to me.......if Royal Mail is so uncompetitive then switch to someone else. It's not difficult. Unless, of course, you find that couriers are just, or even more, expensive and a lot less convenient for most people.
Of course, you could always try delivering your parcel yourself from one end of the UK to the other for £6.
By the way, this has been well advertised in the press, TV and internet. Honestly, if you do business in this area i.e. you send out lots of parcels via Royal Mail, surely one of the things you keep an eye out for is the cost?