Continually Cheaper Utilities Saves Switching

We are forever being bombarded by tv and radio advertisements imploring us to switch our utility suppliers.   Well someone must be making a lot of money when we do, otherwise they wouldnt keep on about it.  I personally have not changed my supplier since way back in 2012.  I had a house lodger then who just happened to work for a utility company during his down time as a hard working university student and he found them extremely nice folk to work with who sold very reasonably priced utilities, especially the electricity.  I signed up with them to get a good deal on my broadband – it was so good that if I changed my gas, electric and home phone too, I got a good contract mobile phone deal.  So I did change and my bills almost halved.  It was staggering how much less I was then paying – and still am.  My electricity is still rediculously cheap compared with my friends and neighbours.