The attitude is the same in most any sport. I am a big gun guy and in the gun world the shop owners are either excellent people are total jerks depending on varying factors.
The guy at your shop is really just trying to tell you that he is pissed that you didn't get your stuff from him and he is gonna "cut you this favor" this one time. Now, my reaction would be to let him know in plain english (or japenese) that you "appreciate" his favor, but you bought from elsewhere because he couldn't even compete with the prices you got and that while you did buy the frame etc... elsewhere you are buuying the accessories from him, unless of course he wants you to go elsewhere.
This type of thing happens all the time in the gun world and I recently had an identical situation (except with a high end rifle) . The shop owner did the transfer for me, but was moaning that I should have bought from him and then he tried to charge me and extra 50 bucks just because he could have got the same rifle for me. I point blank said, yes I could have gotten from him, but I would have paid almost 500 more! I then mentioned how often I come into his store (weekly) and how much I spend on average (about 80 each visit). I then said if he could get the gun for me at the price I paid I would be happy to buy another (identical gun) from him.
I quit going to that store for about a month and then stopped by one day and he rushed over to ask if everything was all right. I said sure, just been shopping around lately. On the spot he appologized for his previous outburst and gave me a 25% discount on whatever I bought that visit.
The problem with bike shops and gun shops is the same, they are small, niche type sports and the average "joe" can easily go to wally world (or another large chain) or use the internet, but they like to support the little guy, small shop owners. Sometimes the small shop owners foreget this and get pissed when we don't come to them for everything, but we need to remind them that we come to them out of compassion (mostly) and are willing to pay extra for the same items we could easily get at a large chain.
just my 2 cents. take it for what it is worth (free).
JOE