What make you think that Antonio is truly a friend to Bassanio?
He is ready to sacrifice his own life for Bassanio. Bassanio, ideally sees him just as some rich friend to be manipulated. Look at how he cares less when Antonio is about to pay his debt. Antonio values Bassanio more than the latter values him. There’s been suggestion of onanism in this relationship too. A friend indeed (Antonio) is a friend in need (Bassanio). The problem is that Antonio is too taciturn and listless to see through Bassanio’s sly espionage. What exactly did Bassanio need the money for? To compete with other Lords and Princes in winning Portia’s love!! Poor Antonio agrees to put his life on the line for such fancies of Bassanio. Yes, that is too much for the asking!!