All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
May Allaah The Almighty reward you for objecting against the owners' decision of giving priority to Hindu bakeries over the Muslims. A Muslim's love, support and loyalty must be for Muslims only. On the other hand a Muslim must declare full detachment from polytheists. Moreover, a Muslim must support the products from Muslims so that their economy grows stronger.
A Muslim also has to boycott the products of the disbelievers, unless they are urgently needed. In fact, such an action evolves around the concept of loyalty to Muslims and detachment from disbelievers that is a fundamental Islamic belief.
However, there is no harm in buying such bread as long as it is the only kind available. The Prophet dealt with non-Muslims in matters pertaining to buying and selling.
Allaah Knows best.