Got two presents this year from a regular: some really nice posh chocs and a free dinner date in the new year (with a paid session to follow). She didn't have to, so was very touched - though I know, as everyone does, that there's no such thing as a free lunch. However we get on really well, and though it's a business transaction at the end of the day it was a really nice gesture. Season of goodwill and all that, and surely best not to overthink?