Charging a premium seems crass to me; how do you explain to the average fan that the already expensive trip to the park with your family just got way more expensive? And you also can't sit anywhere near anyone else.
And call me skeptical or a curmudgeon but personally I wouldn't pay a premium to have to deal with all the added bullshit to go see a game live with only 10-20% capacity. Extra, what? 2x? 4x? so that I could put myself at risk, deal with idiots trying to move seats, ignore the distancing, argue about wearing a mask, not keep distance at the concession, extra time in and out, etc etc so I could watch a game and feel like I'm at the Trop for a Rays - Marlins game? Some would and might, but are 5K fans making a difference on the bottom line? I'd think it'd come close to almost adding to loss for owners once you factor in all the added costs.