Along with speaking harshly to his brothers, Joseph also occasionally treated them kindly, in order to gradually prepare them for when he would reveal his identity to them. Thus, when they all returned, with Benjamin, he prepared a fine meal for them.
Hospitality vs. Austerity
וַיֹּאמֶר לַאֲשֶׁר עַל בֵּיתוֹ . . . וּטְבֹחַ טֶבַח וְהָכֵן כִּי אִתִּי יֹאכְלוּ הָאֲנָשִׁים בַּצָּהֳרָיִם: (בראשית מג:טז)
[Joseph] said to the overseer of his household, “Have animals slaughtered and prepared, for these men will dine with me.” Genesis 43:15

Hospitality requires that hosts try their best to care for all their guests’ needs. Even if they are not sure that the guests will partake of what is prepared for them, the hosts should nevertheless provide abundantly for them.

Similarly, although living frugally is a value found in the Torah, it is one we should impose on ourselves, not on others. When we think about providing for a poor family, for example, we should not provide them with only their bare necessities, but with enough to allow them to live according to a dignified standard of living.1