the point of the draft is to select players who you invite to your training camp, where they work hard to make the team. just because a person gets drafted doesnt mean they are assured a spot on the team.

it just so happens that those drafted first are more likely to make the team than those drafted in the mid- to late-rounds.

so the point here is that sam, as a 7th round draft pick has way more unknowns than vick and has to prove that he belongs in the league.

vick, already having been drafted and having played at the league at a high level, doesnt have to prove he belongs in the league (at least based on pure playing ability).