Hello @Paddi69
Each network offers different plans to compete against each other, all offering some sort of USP. EE currently offer Apple music for example to its customers.
BT Mobile offers the family Sim, I get what what you are saying about users being different but for each sim you get the prices drops thats BT Mobiles USP, that and mose sim only deals are way cheaper than most networks. If all mobile providers offered the same plans and the same prices we wouldnt have a choice.
BT Mobile is still fairly new, and still evolving so who knows what they may offer in the future...