Maybe more usual, but also more headaches, sometimes, if one later on wants to move just one service. Obviously these 3-part or 4-part (VM offering TV, internet, phone line+calls, and a mobile contract) start off cheap with special offers but they're always to attract new customers and once that promotional price has ended, the customer might want to switch part of their service away.
I'm an existing customer of PlusNet and have been happy with them, but recently they've had a deal on where the combination of phone line and fibre broadband could be had with no (or very low) setup fee, and 6 months at half price (9.99 instead of 19.99), plus, if one knew about it, Quidco would pay a further 90 pounds 'cashback' (which may take a while to arrive, but given the minimum term for the Fibre option is 18 months, not that important).
Of course, as a loyal existing customer (soon reaching 10 years with them) I cannot get the 90 quid, or half price deal, and upgrading (even if I took a new phone line {as I want a second line + second ISP}) would mean I'd pay 19.99 plus the fee for the new line...
That's a 150 quid difference between me and a new customer, something I'm not too happy about. (A little academic as Fibre has been pushed back from Sept 2012 to May 2013, but in principle I dislike the willingness to cut prices for new customers and not match or offer something for simple upgrades.