Cs get degrees, but Bs (GPA >= 3.0) improve chances of getting job interviews for the first job out of college*, and As make it more realistic to apply to medical to top 14 law schools.
At some schools, grades higher than C may be necessary to get into a popular major whose enrollment is capacity-limited.
*According to NACE, 70% of companies use college GPA as a screen for applicants from college, and 60% of those use a 3.0 cutoff GPA. See http://www.naceweb.org/talent-acquisition/candidate-selection/the-attributes-employers-seek-on-a-candidates-resume/ . So the 0.02 between 2.99 and 3.01 GPA can make a huge difference in interviews offered.