We replicate in the laboratory an artefactual field experiment originally designed to investigate the incidence of various forms of social preferences in a representative sample of the population. Results show that, on aggregate, the two groups display a similar directional pattern in a set of simple dictator games. However, in situations in which giving is costly (or rewarding) for the dictator, the proportion of laboratory subjects who follow their self-interest is relatively higher than that in the rest of the population. We note a higher sensitivity of students, both from the laboratory and the field, to the possibility of losing part of their own payoff. Furthermore, students from the lab (all economics majors) are more sensitive to gains than students from different backgrounds even when these gains go against equality.