One of many use cases would be to calculate the average of a star rating column (as seen here: Stars or Rating Field Type - #2 by Chr1sG)
This would then in real-time calculate the value, like any other number column. Useful if applying filters over a table. Though you could argue a reporting dashboard could and already does the same thing, I think this wouldn’t hurt to have.
Obviously it would be non-sensical if the select’s numeric value is an ID or something similar. I’m just spitballing ideas.