Called about a crank arm replacement for my Giant....

Called about a crank arm replacement for my Giant. They asked me questions to narrow the part down( guy on phone going back and forth to ask the mechanic).
They tell me they know the part and have it in stock.
I said are you sure as I have a 2.5 hr round trip to come and get it.
Yes 2 in stock.
So I drive down and they say no we don't have that type
They tried to help by selling me a whole crank set at no discount for stuffing me around...
Not good enough.
No wonder internet sales are booming.