Americans and other expats are treated very well by the locals in Volcan and Cerro Punta.
To give you just one example, I was recently at a local supermarket when i saw an American woman coming out of the supermarket with a lot of grocery bags who unfortunately fell. When she did, everybody ran to help her to see if she was OK, and to carry her bags. She told me "If this happened to me in US nobody would help me. But here, it is amazing how everybody ran to help me, even though I am a foreigner and nobody even knew me."
All the local Panamanians help the expats when the expats don't speak Spanish; the locals try their best to understand the expats. Here in Volcan and Cerro Punta, Panamanians and expats go to the same places all the time and mingle easily without any trouble whatsoever.