I know that he is just a guy, but based on my experience, culture has an impact on people's values, ways, and how they do things.
Cultural differences? Poles are much more calculating than Americans. Figure, figure, figure. They're also well in command of their emotions. His feelings may be true ... or he may be looking for a quick piece of bum or maybe something more, like a Green Card. He may be married with children back in Poland...or he may be single and available. You just don't know him very well because you haven't know him very long, and Poles are very hard to get to know. They don't like showing themselves. If you like the Polish personality find yourself a Polish American, than you have the best of both worlds.