Same reason people name roads and food plots on hunting clubs.
Naming roads and food plots is a way, especially on large properties, to have specific identifiers for hunters. "Go down the Pothole Road through the pines, take the second left on the Skidder Trail and then you'll be in the Jones Plot" can help someone not get lost or be able to call for assistance with more certainty.
Same reasoning for naming deer. "Don't shoot so and so" or "shoot so and so". If I bring a guest,I'm definitely showing him/her pics of what bucks he/she should be looking for or passing. Sorry,but we're not a "brown it's down" club and everyone can't score/age deer on the hoof as good as you or the OP can. The fact that you let this bother you is pretty telling. I forsee many roadrage incidents in your/OP's future.
Why are you acting like anyone is mad? I don't have any rage. You sure to protest how important it is to name your deer. If you have a guest that can't age or score a deer, do you really think they can tell one deer from another from a picture you showed them? Come on.
If it makes you feel better, go for it. Apartment, the deer namers like you think no one can have an opinion other than bowing to your awesomeness and superior hunting skills. I don't know how any of the rest of us non namers ever make it.