That's precisely the problem, though: there are so many exceptions. No, you don't say someone is "owning" a car, but:
McDonald's slogan is "I'm loving it." (Love is a stative verb, but has been used in the progressive at least as far back as 1965, when Otis Redding released "I've Been Loving You Too Long.")
"Do you see where I'm coming from?" is a common idiomatic expression meaning, "do you understand my position/motivation?" Yet "come" is a stative verb.
Every stative verb relating to senses and perceptions has an active usage as well: consider ache, feel, hear, hurt, look, notice, observe, perceive, see, smell, sound, and taste.
I recently tried to help my students understand the concept by compiling a list of stative verbs from various textbooks, then putting asterisks next to the ones that can be used in the progressive under certain circumstances. Guess what? More than half of them turned out to have exceptions.
I had another idea for a rule of thumb to help them understand whether or not something could be used in the progressive, without having to memorize so much. We had played charades the week before, so I told them that if the verb was something you could possibly act out, then it could be used in the progressive. For example, the word "indicate" is listed as a stative verb, but it can be used in the active sense of "point out." If you are using it in that sense, it is possible to convey the meaning with gestures.
Unfortunately, I don't think it made a lot of sense to them, so I went back to the lists. Still, I think there has got to be a better way.