Multiple components comprise the Epicurean life. There is more to laud in the "sweetest life" than just pleasure. To say that there is only one highest good, is like saying you can only have one favorite food.
Excerpts from Letter to Menoikos, translation by Peter Saint-Andre:
"Let no one put off the love and practice of wisdom [note] when young, nor grow tired of it when old."
"Practical wisdom is the foundation of all these things and is the greatest good. Thus practical wisdom is more valuable than philosophy and is the source of every other excellence [note], teaching us that it is not possible to live joyously without also living wisely and beautifully and rightly, nor to live wisely and beautifully and rightly without living joyously. [note] For the excellences grow up together with the pleasant life, and the pleasant life is inseparable from them."
And from the Vatican Sayings (translation by Peter Saint-Andre):
"The noble soul is devoted most of all to wisdom and to friendship — one a mortal good, the other immortal. [note]"