In non-tournament settings, every dollar you win at poker comes out of the pockets of another player at the table. It's truly a zero-sum game, as adding up the gains and losses of players at the table will result in zero.
In contrast, tournament games (chess, golf, tennis, WSOP, esports, etc) may have significant entry fees, but at a professional level the total winnings are significantly more than the sum of all entry fees. Generally the excess money comes from corporate sponsors or viewership fees. The entry fees can result in some players walking away with less money than they started, but I don't think this is common outside of tournament-play poker.
The most popular professional sports (soccer, football, baseball, etc) have players on salaries. Those players often also get performance bonuses, either for entire-team results (winning the championship) or personal results (number of games played, statistical thresholds, etc). But they're all getting paid _something_ win or lose.
In contrast, tournament games (chess, golf, tennis, WSOP, esports, etc) may have significant entry fees, but at a professional level the total winnings are significantly more than the sum of all entry fees. Generally the excess money comes from corporate sponsors or viewership fees. The entry fees can result in some players walking away with less money than they started, but I don't think this is common outside of tournament-play poker.
The most popular professional sports (soccer, football, baseball, etc) have players on salaries. Those players often also get performance bonuses, either for entire-team results (winning the championship) or personal results (number of games played, statistical thresholds, etc). But they're all getting paid _something_ win or lose.