The TVs may use the web even if you're not using the TVs, so it's best to do what you did, disconnect them from the internet.
You should not have a problem with just browsing, but if you don't have an ad blocker, you may want to get one. Ads can eat a lot of data. Also, you may want to change your settings so videos don't play automatically, as that eats data too, and many sites have videos that start playing as soon as you land on the page.
Yes, satellite internet is expensive because the technology is super expensive. Terrestrial internet is much cheaper because the technology is cheaper than sending a satellite into orbit and maintaining it, and also because terrestrial internet exists in places where there are many users, so they charge less but have many more uses, so they make a profit that way.
Contact your representatives at the local and national level, and tell them you want terrestrial internet brought to your area. These companies don't come because they don't make a good profit in rural (or other less populated areas) but if the local and/or federal government offer them incentives, sometimes they do open up shop in these areas, as the incentives make it worthwhile for them.
