Of course. However, Dish still publishes their non-promo rates, unlike many cable companies, so at least you know about what you'll be paying when your promo expires.
As we all know, everyone’s experiences are different. I’ve not had that problem. Cox gave a print out of the costs month by month for both my accounts in Nevada and Oklahoma, when I switched.
Just signed up with Comcast last month. Saving a lot of money vs Fios. They told me up front how much I was saving a month off of the regular price. In two years I know my saving will be over.