The same reason a dog licks his balls....because he can.
Yeah, I hate dogs for that too. You see, when a person passes and reaches Nirvana, you are reincarnated as a dog in your final life.
They have it great, and being able to lick your own balls is just one perk.
Sleeping on the couch all day is another. Crap, my dogs eat better than many people do. Steak, prime rib etc.
But, the topic at hand. People buy custom cues for many reasons. The reputation of the maker, the playability, being able to design the cue down to the last inlay.
Of all the cues I own, the one cue that I keep in my case as a back up is a under a hundred dollar cue that I redid myself. It plays great.
I agree with my Bud Joe (Sniper) Building a cue is no easy task. It takes
tons of money invested in equipment etc and a vast amount of knowledge,
which also includes lots of wasted time and materials in trial and error to even think about putting your cues out there in the market.
I stick to the repair side of things and am going to dabble a bit more in the future in building myself. That said, I think I am going to own a ton more cues myself if that happens as I don't have a desire to enter the cue market place. As a hobby alone and 3 lathes later, supplies, a river of wood sleeping in the shop, plus other necessary types of power tools, I think I have close to 12 to 14 K invested
and that is just for hobby purposes. Many have much more than I.
So yes, when a cue maker hits his place in line, he has to charge for his craftsmanship and when you consider that if a cue maker were to charge accordingly for every minute of his time, custom cues would be more expensive ten fold.
Just know that whatever decision you make regarding a playing cue for yourself is going to be the right one.