I have learnt that the pilots within these groups, generally, are only interested in their types,
Actually I find the same thing. To each their own, I suppose.
What I find worrying though is that both communities (glider and VFR/PPL) don't seem to have a grasp of each others operating characteristics, and therefore get into habits that make things unsafe for themselves and for others. A little understanding of the other groups would go a long way in making things safer for both groups.
Examples are powered aircraft transiting glider fields with winch launches at low altitude, but also gross misuse of transponders (mandatory, even for gliders, in NL) by the glider community (leaving them on "alt" while being launched for instance - against all advice in the AIC).
And as far as records are concerned - well, every sport has these endurance types but they form a very small minority. My estimate is that both powered and glider pilots are quite satisfied with flights lasting two hours or so and will only very occasionally do flights longer than that.