I love getting Christmas gifts for my cats, when I can. Last year, this current group of cats (my gypsy tribe of semi-ferals) had just showed up not long before and I had to admit that getting something for them for Christmas would be totally wasted. Meaning, they had no clue about Christmas! and I was already buying stuff for them on the off chance they would come inside (they still have not) and that was not going anywhere. (And I do believe inside pets understand enough about Christmas that they can appreciate gifts - they sense something celebratory is happening and like to be included in that.)
I've decided to focus on spending my energy toward keeping them as healthy as I can since they are outside - so far they're doing pretty darn well from what I can tell!