Why Soccer Is Theatrical, in a Mathematical Nutshell

Size of NFL field: 48000 square feet.
Number of players: 22.
Number of guys with whistles: 7.
Formations: Players largely concentrated in one part of field.
Probability of something illegal happening: high.
Official eyeballs per player: 0.636
Official eyeballs per acre: 14/(48000/43560)=14/1.102=12.705

Official Eyeball Coverage Quotient; 0.636*12.705=8.080

Avg. size of FIFA regulation field: 81000 square feet.
Number of players: 22.
Number of guys with whistles: 1.*
Formations: None. Players all over the field at all times.
Probability of something illegal happening: high.
Official eyeballs per player: 0.273
Official eyeballs per acre: 2/(81000/43560)=2/1.859=1.076

Official Eyeball Coverage Quotient: 0.273*1.067=0.294

8.080/0.294=27.484

So it's 27.5 times as likely that a ref will see a foul on a football field as on a soccer field. If you were a player, you'd try to get that ref's attention too. Then there's the question of how widely spread the players are...difficult to quantify, but another factor that would increase the differential.

*3 if you count linesmen, who occasionally call fouls but are mostly there to flag offsides and out of bounds; when and if they wave their flags to make calls, the ref can wave them off and allow play to continue. But even if we grant 3 "refs" in soccer, the difference is still nearly a factor of 10.