The former Spain international feels Los Blancos already have sufficient options in attack, but admits the winger would still prove to be a good signing
The Liga giants are keen to lure the Welshman away from his current club, but have so far been reluctant to meet Spurs' €115 million valuation of the 24-year-old.
And Sanchis feels that Bale's price tag could ultimately prove to be too much of an obstacle.
"Is Bale absolutely necessary? I don't think so," Sanchis was quoted as saying by Marca.
"But if he comes, he will be a good option, a very good one. The problem is the price..."
Sanchis then went on to stress that the potential arrival of Bale would not affect the development of the club's own youth players.
"I would not link the progress of the youth team players to the signing of Bale," he said.
"At Madrid, both types of player have always had to learn to live together and the results have been good. There are also cases of big signings at the club being shown up by youngsters with less experience."
The 48-year-old Sanchis made over 500 league appearances for Madrid between 1983 and 2001.