Mostly BC-itis, I'd say. Berger usually tops the BC listings, in some cases by a lot.
What a lot of people forget is that while getting the ultimate combination of precision, velocity, and ballistics is really important for long-range high level competition, the velocity+external ballistics bit becomes steadily less important as range decreases and a really accurate combination often trumps everything else at short to medium ranges, shooter skill and wind-reading ability etc, etc being equal of course.
The trouble is that once exposed to 'the ultimate' and tricks like bullet sorting, pointing and all the rest, these things become addictive. A .30 168gn Sierra MK load might shoot into a single hole at 300 yards, but a little voice in the back of the mind says that you still need something with 20% higher BC just in case the SMK sees you leak out that fatal extra quarter inch and drop a point in a sudden wind switch, or you lose out to that guy in the club you're determined to beat this season by a single 'V' ('X' to most people here).
I've got a large consignment of Sierra 7mm 180s lined up for purchase at a very good price compared to Bergers, but most F-Class shooters here won't use a Berger VLD these days never mind a Sierra - they'd go out on the range trouserless rather than give their 180gn Hybrids up.
FWIW, Lapua's bullet design policy puzzles me. There is always one really good long-range high-BC design in every calibre, sometimes more than one ... but the remainder are usually pedestrian. The two completely new-design .30 Scenar-Ls comprise a nice but hardly inspiring 175gn whose claimed BC is only marginally higher than that of the 30 year old 175 SMK, and a 220gn that everybody assumed and hoped would be a competitor to the 215 and 230gn Berger Hybrids, but which has a very modest BC, relatively short and blunt front section, and a HUGE long bearing area that'll generate vast amounts of pressure. With growing interest in the .300 WSM as a L-R competition cartridge here, Lapuas readily available, and Berger Hybrids on back-orders months before they arrive, this bullet could and should have been a rip-roaring sales success from day one. Instead, I don't know anybody actually using it. The 180gn 7mm is 'better' in that sense, but is again generating nil interest and take-up amongst our national level competitors. I've tried the 150 7mm and it generates an awful lot of pressure in my 284 for reasons I don't readily understand, so although it shoots well as a short-range bullet, MVs are very low. The 'L' consistency is fantastic though, but I think there is resistance to paying near-Berger prices for bullets with lower BCs.