This is just one part of the debate over 'Net Neutrality'. But one argument the telcoms make against Net Neutrality, actually their main argument vis a vis consumers, is that they need these extra fees to build out the next generation of super-slick new mega-internets that will leave today's internets in the dust. There are various answers to this question. But one point to keep in mind is that with every new big telecom bill the telcos promise all sorts of new stuff. And their record is, in a word, terrible.
So what the telcoms want is a whole new class of customers (all websites, basically) they can extract fees from. And the rationale is because they'll build all this new stuff. But they've said stuff like this many times. And usually they don't follow through.