A transfer request doesn't do an awful lot of anything, it can reduce the effective price as it usually means a player isn't due their loyalty payments, but it doesn't force the club to sell. It's not in the players interest to put in a transfer request as you lose money. So ultimately a release clause that both doesn't cause a release, and at best might lead to putting in a transfer request that loses you money... when everyone else has a standard release clause that means the club accept and you get your loyalty payments.
Contracts are a negotiation, lets say Ronaldo, he signs an insane wage deal with a huge wage rise and also has a 1billion buy out clause, it means Real have secured him. He could turn down that clause, but the club are less willing to pay him so highly as with a sensible clause for Ronaldo, say 100mil, they might lose him and have to pay out a huge loyalty payment. So to get a lower release clause they would concede elsewhere, lower wages, lower bonuses, etc, etc.
Having a lower and sensible release clause put into the contract that the club can't refuse would almost certainly also come with a negative point for Suarez, IE we want to leave if someone offers 40mil, we'll take lower wages to have that clause in.
In what negotiation does putting in a clause that doesn't help him leave the club make sense at all but also likely came with a down side, none is the answer. He's getting precisely nothing out of that "release" clause, and both Liverpool and Suarez are calling it a release clause. Classic bait and switch if you ask me, show them a contract, they read through it, just before signing someone says "wow, look at the boobs on her", Suarez's guys all turn around and LIverpool guys switch the contract for one with a crippled release clause