I dare say that shouldn't be the case.
USE="tcl" means to install Tcl bindings, which require Tcl at run time. Besides this, SQLite build system unconditionally requires Tcl to process source files (before compilation). (See also bug #724578.)
*** Bug 733930 has been marked as a duplicate of this bug. ***
*** Bug 829112 has been marked as a duplicate of this bug. ***