It is (offered) in the way of Allah. The Messenger of Allah ﷺ said: For this you will have seven hundred she-camels on the Day of Judgment all of which will be muzzled. (Using translation from Muslim 1892a)  

رَسُولُ اللَّهِ ﷺ «لَكَ بِهَا يَوْمَ الْقِيَامَةِ سَبْعُ مِائَةِ نَاقَةٍ كُلُّهَا مَخْطُومَةٌ»