The whole mood of the vrata is that it’s about Kṛṣṇa, but here it’s just all about their inconvenience of fasting. So better they not fast. They will get more spiritual benefit.

Kṛṣṇa, Who, being God, could eat anything, He has chosen these particular things to eat because out of all the different tastes they are the most developed and refined. So it is a nice direction to go towards. But I would say more important is to learn how to cook.