ELO system works if people from regions and leagues of different level meet. More often they meet better calibration is. In CZ it's simply by fact that many people (such as me
play in several leagues so top/down calibration works pretty well. Cross regional might be a little problem but because of 4 nation-wide levels even that works. In most regions system works for 5+ years so ELO should be pretty accurate now. It's kind of a question which system calibrates better: "USATT like" with mostly individual tournaments spread across the country where calibrations is done only thanks to people traveling longer distance (
do price money exist there? if not the motivation of challenging people far away and pay $500+ for the trip is questionable from my point of view) or "hierarchical leagues" where most of the people meet just their neighbors but very frequently and few people spread the information among regions by playing district/state or state/national level during the same season (btw. even the fact that each year 8-10 new people come to the league with 2 advancing teams from the league bellow and another 8-10 new people descending with 2 teams from upper level spread the ELO comparison over the years pretty well).
Probably enough about USATT and European ELO based rankings in this thread?
Prize money exists in most large tournaments, but it is either a) concentrated in the Open division, or b) even if offered in lower events is usually not enough to cover the costs of participation. So, I think it's a fair statement that most people (especially lower rated ones) attend these events NOT because of the money.
Why do they go there? Great question, perhaps deserving its own thread. Speaking for myself - I enjoy playing TT, it's my hobby, and I view trips to US Open/Teams etc. as a very nice vacation. Some people like going to the beach, hike the trails, visit new countries etc., I like playing lots of TT, preferably in a reasonably interesting place. Probably would go to a TT camp as well, same thing. Tournaments provide a measuring stick of your progress (rating is a good indicator of your level, not perfect, but easy to track) and it is natural for people to try to get better.
You obviously also have up and coming juniors, for whom it's a great opportunity to validate their training, gain experience etc. Coaches and semi-professional TT folks presumably play to maintain their level/reputation and they actually have legitimate shot at some prize money. Pretty sure they are competitive by nature as well.
Hope it explains it somewhat - bulk of players at these events are not pros, just TT enthusiasts. Most can afford it, and 1K/week is not that much, as far as vacations go (IMHO, of course, plus don't forget that incomes in the US are somewhat higher too).