Personally I don't care what people want to be known as or openly label themselves. They are all cyclists to me. Why divide the community by what bike one chooses to or can afford to ride? The bottom line is if the bike does what you want it to and fills your requirements. It's as simple as that. Everybody has different abilities and some are better than others in a few disciplines...so what? Give them kudos and move on. Whenever there's a get together, organized or impromptu gathering, does one want to show off or "win" or is it mainly to socialize and make new friends and renew old acquaintances?
Is a person that has the bucks for a top-end bike that is kept in like-new condition or constantly upgraded with the latest parts and only ridden in organized events any more a serious bike rider than somebody with a *-mart bike with an egg crate box on the back to haul groceries and uses their bike on a daily basis?
I could care less if one wants to wear a full Lycra outfit, business suit, swimsuit, or a t-shirt and jeans. Whatever one is comfortable wearing is fine in my book.
If one is participating in a highly competitive racing event, then that's a totally different. One would want to get every edge possible and leave it up to ability/talent and decision making to win a race.
But if one just wants to get accepted by some local group that has "conditions", then you have to decide whether it's worth it or not to become part of that clique and gain recognition as being a "serious cyclist".
Everybody will have their own idea/definition of what they consider what a "serious cyclist" is. My main point is not to look down on people that may have a budget that limits their buying options/choices or finds a model that has the equipment they want, but may not be the flavor of the month bike. Plus the majority of bike buyers would rather buy a new bike rather than an used one...even if the used bike is considered a better buy/choice. My neighbor, another daily bike commuter, just bought a Schwinn World DBX and is extremely happy with his purchase and feels that it's flexible and fast enough to compare favorably with his old road bike (he wanted a dropbar bike with bb7 disc brakes). How many at this or any other bike forum would tell him he wasted his money and that he wasn't a serious cyclist because he made that purchase decision?
Sorry about the rant...