Originally Posted by don d.
Real racers are much more concerned with keeping the bike rolling through the season than keeping the bike "stock" for the next retro bike show. They will replace parts with whatever works. They often have more than one set of wheels, so the different hubs, parts, etc... are not unusual.
I have to disagree with this, at least for a top amateur/pro squad like Team Crest. The equipment is supplied by the sponsors. A team at this level has very high visibility and any substitution would make those sponsors VERY unhappy. This current equipment would have been put on after the bicycle left the team. Whomever was the last team member to have his hands on the bicycle probably stripped the good stuff and installed what the had lying around.