one on ones during campus visit Do all schools have candidates at tenure-track campus interviews meet extensively with faculty members and administrators one-on-one? Are there schools where it is customary to devote a campus visit primarily to group interviews (faculty and students), job talk and/or sample class, tours of the facilities, and meals (with faculty)? Basically, does such a schedule signal lack of interest or is that the usual in some places?
Whatever the schedule is, it's almost certainly identical for all candidates.  You can't deduce anything about the school's interest from the schedule.

The way my department does tenure-track interviews, the only one-on-one meetings are with the department chair and the dean.  Other than that, there are, as in your description, group interviews with faculty and students, a research talk, a sample class, and meals with a group of faculty.  The schedule doesn't include one-on-one meetings with individual faculty.  And this is the same for all candidates.  

(This is a mathematical sciences department at a medium-sized public university in the US.)