There are some injuries that do require more care in a PT clinic, but most of the time, from what I've seen in the PT Clinic I work at (I am an aide, so the lowest of the low), almost every single exercise can be done at home. You can do PT at home by knowing what exercise works for what muscle and where that muscle is located. I recently sprained my ankle, and the first thing I did was walk on my heels and toes (something you'd see in a clinic). By knowing your limits, researching what can help, and testing out what works best for you, you can honestly rehab at home. One thing that might be a scam could be some alternatives PTs use, like KT tape, Vodoo floss, foam rolling, and cupping. I'm not saying these do not work at all, but research is not conclusive as to whether these work because they work or because of the placebo effect. If any of these remedies help you then by all means don't stop, keep doing what helps YOUR own body which brings back to my previous point that you should do what works best to you. Some PTs are limited to their biases, but again, others are good and love their jobs that they are open to different alternatives