I am usually the last person to criticize others on this forum for wanting to present themselves in a better way. But what you did is simply not acceptable, regardless of what dental schools think.
It's fine to go on those trips (I did!), it's fine to help with patient management. I won't even criticize you for helping with cleanings. But extractions and restorations?! There is a perfectly capable dentist in the room...let them do it.
Would you want some random person with like a day in training extract your tooth/do a restoration? If you aren't willing to have the same done to you or a loved one how can you do it to others?! If you are willing to have this done to yourself, then that's a problem too.
What's done is done. But please reflect on this. Not only now, but also when your a dentist. Just because you have a piece of paper saying you can practice dentistry, doesn't mean you should. Every case is different and sometimes you will need to refer some cases to someone that is better able to serve the needs of the patient. Even if that means loss of money or admitting you can't handle a specific case.
Sorry if I sound harsh. I'm sure you meant well. It is clear you didn't realize you were doing something wrong by the mere fact you are asking if it's frowned upon.