I hate to be a bad guy, but I'm skeptical that someone didn't get the job because they ride a bike. The only reasons I could see for that being true are such as what Machka mentioned where some car use is needed at times, or they assumed you didn't have a drivers license that is sometimes needed, or that you are expected to dress/appear in a certain way that is more difficult for cyclists to do (aka suit and tie and the company has no shower room). If it's not for one of these reasons, which if it was probably had some sort of clue in the job posting/style of job, then I would think that they are just being nice and not telling the OP the real reason.