I just went through this. I am one of those guys whom has a few hobbies, and none are cheap. Bikes included. I get nothing but the best, as well. My fly fishing gear, stereo, bike....all high end.
I basically told my wife that I was getting a new Chromag Surface Ti, and that was it. Granted, I am the 90% earner, but the fact I am getting older (45) also puts me in the "I don't give a shit" category. Life is too short for regrets, we are not hurting, and as my wife said to me last night "you can't take it to the grave". Not that one should be foolhardy and be swallowed in debt, but some long term financing is okay so long as it can be paid and the bases covered. Of course, the final bill for the new bike is not mentioned, but the understanding it is going to be "significant" is there, especially with my given proclivities for nothing but the best. By now my wife has most likely adopted an attitude of "don't ask, don't tell". And truthfully, she is treated very well.
I suppose it depends whom really wears the pants. I think age has something to do with it, too. If I were late 20's early 30's and struggling for a down payment on a townhouse or whatever I could see the debate. But if you are established and comfortable.....full steam ahead.