I don't think it's that big of a deal, aside from a chuckle. The riders aren't brand-loyal - they're after performance. They're paid to advertise their sponsor's brand, not prove it's worth in competition (depending on the sponsorship contract, of course).

It brings to mind a paintball tournament I was in a few years ago. One of the teams had a sponsorship with one company, but wouldn't play with any of their gear because they preferred something else. They wore sponsor patches and stickers on their clothes and gear, though. And when they won their trophy, they had their huge sponsor banner out and made certain to thank the sponsor. Incidentally, a few months later I was chatting with a player on a different team with the same sponsor, and they were required to use the equipment in tournaments. Just depends on the agreement.