Culture and expectations? What I absorbed growing up was that you don’t tip business owners and professionals, but as a professional that’s worked in a few different fields, some people these days want to tip for everything. (I used to eat occasionally in a restaurant that had a strict no-tipping policy that instead paid their waitstaff a real living wage, and the amount of hate they got for it sometimes was surreal.)
That said, I totally don’t think of holiday gifts as tips, and I totally give holiday gifts to some professionals. What I aim for is something somebody would like but that they wouldn’t have gotten themselves, but if I don’t know them too well something tasty, a bottle of wine, or even cash works. Totally optional, though, and the core message is “I am thinking of you and wish you well, here is something nice”, not “I’m trying to buy better service” or “this is an expected part of our transaction”.