I'd love it if my low carb cake was left just for me! Indeed, at home, family is forbidden from eating my low carb goodies. Especially they are very costly to make.
There are plenty of easy, cheaper choices for carb eaters, so let them eat their cake, and hands off mine!
Seriously though, they may just have been being polite, or unsure of anything new or different. I remember years ago taking some traditional English bread pudding into work and feeling very hurt that no one, especially those from non-English backgrounds , would even try it