Goal or Not that is the question

I expect a lengthy comment from Grocer Jack on this but I do not understand the problem with the Man U/Spurs contention. They are now trying to suggest that there is some sort of laser detection system put in place around the goal post frame to detect if the ball crosses the line. The ball was clearly over the line, any idiot could see that, and I watched the game live. It was filmed by hundreds of cameras including the live match camera which displays the action in the ground as it happens.
In Rugby the ref has a live radio link to the touch judges and a match official and if there is contention over a touchdown calls for a video replay before he makes a decision, why can't this happen in football- answer - because there would be no controversy and no material to fill the final 10 pages of any tabloid!