Somehow, to me, this looks like Cargo cult programming.

The only mention of autocommit in SQLite docs is this, which says

Autocommit mode is on by default. Autocommit mode is disabled by a BEGIN statement. Autocommit mode is re-enabled by a COMMIT or ROLLBACK.

Basically this makes me think SQLite would ignore any attempt of the application to set such a flag.

Update: Of course, were it MySQL, your findings would be plausible...