I grew up in Germany and have done some business there over the years (been living in the US for nearly 25 years now though). From my experience, a lot of companies will not allow this sort of thing, unfortunately. Small business and self employed individuals are more open to it, of course, but anyone working for a larger company will likely have something in their employment contract prohibiting them from accepting gifts of material value (anything beyond lets say a pen or a sticker / mousepad / etc., some specify a limit of 5 or 10 EUR).
This also can extend to buying prospect lunch or dinner, although I have found that the people are more willing to bend the rules in cases like that once you’ve established trust and have a relationship.
