Smith is a sports lover and often spends his weekends attending sports events. This week, he has two important events, a baseball match of his favorite team and a soccer match where the team he supports will play to qualify for the semi-finals. Unfortunately, he has a limited budget and cannot attend both. He visited the previous matches of both the tournaments. The baseball match tickets are valued at $30 while the soccer match tickets cost $42. He habitually buys snacks while attending matches, and his favorite food item is available at $10 at both the stadiums. 

Identify the relevant costs. Explain your answer.