Does your utility bill go down after you've been a customer of theirs after X amount of time? Does your car payment go down after X amount of time? Does your mortgage payment go down after X amount of time? Does your rent go down after X amount of time? Do any of them give discounts for being a customer for X amount of time? Why would you expect DirecTV to do that?
I understand your point, but you are generalizing.
As mentioned about other states, in Texas we have a choice of electric providers. So its competitive and prices do fluctuate. My rates with the same provide have gone down, when I renewed for another 12 mo's.
Another example is Boost Mobile prepaid service. The monthlies go down, based on the length of time that you are a customer. Unlimited talk, text, web is $50 for the first 6 mo's, $45 for the next 6 mo's, $40 for the next 6 mo's and $35 for the as long as you are a customer.
So to answer your question, there are some providers that do go down after x amount of time.