Why is this unfair? Man Utd wanted 6m for a player they weren't offering a suitable contract to. Spurs offered half that figure. He can join Standard for free, so he did.
If anything the tribunal system is unfair. Clubs can make stupid valuations for players they don't even want. If Man Utd had offered a decent contract and showed they wanted to keep him then maybe he would have stayed. As it is, though, he was out of contract. So Man Utd have lost out through their own greed and being unreasonable.
The second time now, after Pogba.
However, these experiences won't change their policy of poaching kids from Belgium, Italy or Holland, or Brazil and manipulating the work permit system where necessary. Look at their youth team, there are several kids there that have been poached because they can sign a stronger contract in England at a younger age compared to in Europe. How many times have Man Utd been investigated for poaching players? Loads and loads. Le Havre over Pogba, Fiorentina over Fornasier and Gollini, Parma over Rossi. As well as other youth players from Liverpool, Emirates Marketing Project, Chelsea....
The difference between these and Fryers is that Spurs tried to agree a fee and couldn't because Man Utd wanted to rip them off. Now Whiskey Face is tinkled that someone got one over on them - despite admitting Spurs did nothing wrong.