Most of the shops in my area do not stock much of anything other than new bikes ,clothing ...

any parts on the shelf are items that move fast, chains , tubes, cables, brake pads , brand name pre -packaged thread less stems , some tires (good luck finding 32 in 700) , tools ETC.

maybe 1 rd 1 fd no cranks, some pedals, enough bolts spokes ... for emergency repairs

I went to one shop thats on my way home from work that sells High end bikes and inquired about white cable housing , he looked at me like I had 3 heads he chuckled "Not Here"!

of all the LBS I have 2 are pretty good, but one is 50 miles away , the other is 16 miles .

1) they only sell and service bicycles , no skis , skate boards etc

2) these bike only shops have a fair amount of NOS stuff and will keep/sell used items taken off of serviced bikes.

most of the LBS (a good friend of mine manages a big shop) Most i've found keep parts to a minimum and are loaded up with New bikes and accessories (that's where the $ are) and if you need a 1 inch threaded headset , they will be happy to order it and you'll see it in 2-3 weeks.

the bike only shops do OK on the parts stuff though its hit or miss but often theyll have an NOS item that will work . Online is always better / more choices.

local shops are not geared to DIY types. they expect you to leave your bike and wait for parts to come in they'll call when its ready.

"John"