SSS stadium owners are generally notoriously picky about field conditions. It was sort of a 'gasp' when DC United made arrangements for the XFL team to play in Audi Field and a lot of consternation about the state of the field during the short overlap. Yard lines are also considered a nuisance by soccer fans. But they were able to use some sort of weird paint that fades fast or some such for the XFL games and they were minimal for the soccer games I recall. Last game for the XFL was done and the ENTIRE field was resodded.
Heavy props are not kind to keeping the field without weird dents and bumps and particularly during the season (and if it's been rainy at all) stadia will protect their fields for soccer. We saw this with the West Chester show where DCI fans loved Philly's stadium but the stadium ultimately got snippy over the state the field was left in for the Union.
That said, Indy Eleven isn't MLS. I haven't read if they're going grass or FieldTurf. They teamed with IUPUI's field for FieldTurf where they play now.