I've been there for purchasing brake parts for my very basic bicycle. I asked for service and they let me wait 10min while those guys had nothing else to do but joking together. Ok, whatever. When asking for what I needed, they wanted to charge me $45 for 1 cable, 2 pads and a small stuff broken on my cantilever brake!! On a basic bike website, you find those parts for about $10. I guess those guys only want to sell the most expensive items they have in stock and don't really care of what you really need.
Another good way to get an idea of there business is to go on there website. Click on "how to fix a flat tire": and learn that obviously the only way is to buy a new one (probably on Wells St) and to replace it...money money...