I think there are two parts to that answer. One is connectivity. As Dane suggests, campground internet is rarely fast enough to support streaming video consistently. At all the campgrounds I've been to, watching streaming video on the campground wifi has been a fail. However, if you camp in locations with good cell coverage, and you have the right data plan, streaming video can be quite effective. I am grandfathered on the verizon unlimited plan and stream video and music while camping often. But you better watch your data limits if yours isn't unlimited! I've used as much as 10 to 12 gigs worth of data in a month streaming video and music.
The second issue is content. You'll have to have a good "over the air" tv signal from local TV stations to watch anything live (local news, sports, weather updates, etc.). Depending on your location and viewing needs, this may or may not be an issue. With a subscription to Netflix and Hulu Plus (less than $20 for both)+ a couple of network web sites; you can stream almost any TV show a day or so after it airs plus have access to hundreds of movies on demand.
I personally would love to stop paying Directv for my home and coach. What stops me are live sports that I can't get over-the-air. Nascar, Football, and College Basketball are often only aired on cable networks. In the end, you have to evaluate your specific situation to determine if "cutting the cord" (or dish) is the right thing for you.