Across the country it suffers from being a niche part of a niche activity
You're either lucky enough to have somewhere nearby who find it viable to have sup air and to set it up, or have to travel. Let alone have an up to date millennium field and have the business to sustain it
The U.K. is small enough to have a great venue sat in the middle of it which is accessible to people who can afford regular tournament play
By the time you've paid for 5 CPPS rounds ,the hotel for Saturday evening ,training and the fuel up and down ,there isn't any spare cash left for local tourneys.Only GI Retribution and Top Cats go on to play Millenium. The success of the CPPS ensures the longevity of a dedicated ,national series and standards local events can only dream of . The southern teams have voted with their feet. The fallout from that decision though is plain to see. With the reopening of 141 at the Gatwick site there is a chance that if enough people are resident training teams .That a tourney there could become viable.
Bricket Wood hosts the Southern Paintball League, with 6 events this year. Two divisions (mercy 2 and 5man) with around 8 teams each round. It's the main series for some teams who can't make it to CPPS, others such as Cardinals and Thunderducks use it as training for CPPS.
There are a few less teams this year though, after a some team breakups or progression to CPPS. Plus as Shoaibaktar states the cost of playing in two tournaments adds up pretty quickly, or real life hits.
BW also host a "fight club" training/scrim day for Elite/D1 teams before each CPPS.
One41 was hosting a tournament at their old site, will have to see what happens with the new location.