The team set an American League record on Wednesday after scoring their 21st consecutive win against the Detroit Tigers.
As the Indians prepared to play Thursday night, tickets were still available.
"There's some tough structural conditions in Cleveland that we recognize, especially as you get into the school year in September. Weekdays, it's a little bit tougher to get down to the ballpark," Mike Chernoff, the Cleveland Indians general manager, told CNBC's "Power Lunch" on Thursday.
He said Cleveland's size is a contributing factor to their unfilled ticket orders.
"We are a relatively small market. You compare us to a city like New York or Los Angeles or Chicago and there are just some things that we can't match up on in terms of population and some of the wealth of the population."
Whatever the reasons fans choose to stay home, Chernoff will always prefer seeing games in person.
"Watching a baseball game in person is a special thing," he said. "There are things you just can't re-create on TV that are so important to this game."
Though stadium seats aren't selling out, TV and radio ratings have soared.
"Northeast Ohio is a really loyal place, and very supportive when their teams are doing well. We're starting to see that now, and I think that's been really fun for the whole city," he said.
— Reuters contributed to this story.