So what you are saying is that the overcall cost of doing business with tmobile (both monetary and your personal data being public) justifies the convenience?
I could tell a horror story from Verizon about a multi-thousand-dollar roaming bill from someone I knew, from Google about being completely locked out of a phone number forever from another person, and lots of others.
Pick your liability.
On the whole, I found the risk of data theft from T-Mobile to be the lesser of the evils.
All that said, Comcast Internet's business practices is outright awful - they lied to me multiple times about my plan and discounts. And you need Comcast to use Xfinity - it's very expensive otherwise.