too busy fighting on the streets
Its shit tournament crowd is only semi final and final
In US, everyone can't get a day off like in for example Sweden. This means people are at work when the quarters would be played in the arena, which would lead to less tickets being solved and less revenue for ESL who obviously have to pay to have the arena.
They probably made the conclusion that an extra investment for hiring the arena on Friday isn't worth it, since the ticket revenue would be too low.
Ever heard of timezones? And half of this event was held on weekdays where people are at work or school. If it was a vacation week or the weekend then the arena would be packed.