They survive by just eating hard substances like Pipe, Electric wires, cables, papers, etc. As you know their teeth continue to grow over their lifespan.
Rats can be found in households. If we talk about Indian households, They easily contaminate food items and property.
Those creepy creatures can easily be found.
They are one of the primary reasons for the contamination of food that’s why our family gets sick. It feels like they are more dangerous than Thanos, But no worry we are Thor for you.