The Quidditch Cup takes place at Hogwarts with each new school year. The four houses are considered mini-leagues and only the four houses compete because this is a Inter-House Quidditch Cup. Each team (House) plays three games and six overall of Quidditch for Hogwarts to enjoy.
All games are attended by students, professors and staff. Each game does have a sports announcer as well. Since there are so few games throughout an entire school year everyone eagerly waits for each game. Even the professors and staff get rowdy like the students do.
The Quidditch Cup is a silver trophy with four handles that represents he four houses. The Cup is traditionally kept in the office of the winning house in the Head of House. The end results are important because their are house points at stake and students take strong pride for their own house. It is unknown what the points system is for the winning team but our guess is maybe more then 50 house points or so.
“This… is the Golden Snitch, and it’s the most important ball of the lot. It’s very hard to catch because it’s so fast and difficult to see. It’s the Seeker’s job to catch it. You’ve got to weave in and out of the Chasers, Beaters, Bludgers, and Quaffle to get it before the other team’s Seeker, because whichever Seeker catches the Snitch wins his team an extra hundred and fifty points, so they nearly always win. That’s why Seekers get fouled so much. A game of Quidditch only ends when the Snitch is caught, so it can go on for ages”
– Snitch and a Seeker’s job (Source: Harry Potter Wiki)