I think the energy companies do have an unofficial cartel in that they all us the technique of obfuscation, all put their prices up by similar amounts and all rely largely on customer inertia. But it is still possible to shop around for better deals and far too few people do it. Also many are still paying by the inefficient and more expensive method of paying quarterly rather than by monthly DD or are not taking account of online billing discounts.
I don't see anything wrong per se in paying bonuses- such schemes can be a good way of encouraging certain behaviours and outcomes in business and rewarding those who meet targets for things like customer service, efficiency savings etc.