Why did Blanche of Castile suppress the Pastoureaux movement?

The Pastoureaux movement of 1251 was a popular uprising of peasants in northeastern France, initially motivated by religious fervor and loyalty to Louis IX following his military setbacks during his first crusade against the Muslims.12

While Blanche of Castile, acting as regent, initially supported the movement, she suppressed it once the participants began pillaging churches and towns. The movement’s focus shifted from its original crusade-oriented enthusiasm to agitation and violence against the nobility, clergy, and bourgeoisie, whom the peasants accused of indifference toward the king’s fate. To maintain domestic order and protect the social hierarchy, Blanche had the movement dispersed.12