I do them to send to friends.
I am actually planning on taking the photos tomorrow, I do it myself, Set the background of a black sheet on an armchair, play with the cat till she is nice and relaxed, pop a bit of tinsel around her neck under my constant watch and tease her with another piece while my other hand goes click click click and then check my photos, when I have one good enough, I remove all tinsel and replace with treats for being my model.
My cat is my baby and all my friends "know her" in real life and online, some of them are fur mummies as well. Perfectly acceptable to do this, I generally get a load of photos together and work out how many photo prints I need an approx example for Xmas cards so +20 and get that amount printed,
Same applies for those who send me cards with themselves or in most cases their children on, or something one of the children has drawn printed on the front cover.
Then I get photos I have taken at other times minus the tinsel which will be made into general cards. So by getting a bulk lot of photos printed ready, glue dots and blank cards. Inside the blank cards, I put a poem or whatever just like a real-life greetings card and then leave room to write my message.
So its a YES from me