Found many strange phenomena in my hometown

1️⃣ Parents who scored over 20 in high school math are teaching their children homework
2️⃣ Winning or losing a game of mahjong equals a month's income
3️⃣ Every household must buy a car but keeps it at home, going out to work by subway
4️⃣ Never go for a health checkup but are willing to buy expensive health products