they will be week-enders But seriously should not make that much.... Rugby Union has it ( well in the internationals for sure) and it does not make too much of an add on. However they do not play stoppage time as the clock is stopped each time the ball goes dead.
and Rugby union. There are a number of things that Rugby Union use that would benefit Football IMHO. Time keeping , each time the ball goes dead the clock should be stopped by an official time keeper and restarted when it goes back live, also this would stop the the so called stoppage/injury time.. Injuries, allow a sub for an injury (blood injury its called in Rugby) when the injured player returns the Blood sub goes off, but it does nor detract from the allowed 3 subs. They have made a rule to stop the trudging off of a subbed player by saying he must exit at the nearest point... this is nonsense as all they have to do is signal to a player to be subbed and he can go and stand on the center spot. thus wasting time , a time keeper (clock stopped) would stop all this nonsense.
I'm sure it won't be too long before players agents are asking clubs for time and half for any additional time spent on the pitch.