Former Packers general manager Ted Thompson almost always used his allotted 30 pre-draft invitations to the Packers' facility on prospects that projected to be undrafted free agents. He almost never brought in prospects who were slated to go early in the draft, some would say because he didn't want to tip off opposing teams on who the Packers were thinking about selecting early on in the draft.
Thompson's protoge and current Packers GM Brian Gutekunst took a very different approach last year in the run up to the draft, bringing in several prospects who were expected to be selected early on in the draft.