there is perhaps some (a lot) of truth in this statement, however, I ride sportives and don't fall into any of the above. I would certainly NOT recommend 'group' riding on sportives due to the lack of riding skills that exist amongst many of these middle aged 'lycra louts'. However, I plod along for the 100 miles or so on my own and really enjoy the signed routes etc. Annoys me when some random gets on my wheel though - excuse me, do you like looking at a stangers arse or what?
For some reason, a newbie on a very expensive bike seems to annoy most people. I personally don't care at all as long as they stay away from me - especially on descents. After 25 years as a serious cyclist I was more offended when my new bike was descibed as 'entry level' especially after spending over £1K on it!