Tell my friends to which "comma club" they belong
JavaScript (ES6), 80 bytes

a=&gt;a.map(([s,n])=&gt;s+` is in the ${n.toFixed(n&lt;0?3:4).length/3-2|0}-comma club.`)


Takes an array of [friend, amount] arrays and returns an array of "friend is in the n-comma club." strings. Works by adding extra trailing zeros so that the length is 6-8 for the 0-comma club, 9-11 for the 1-comma club, 12-15 for the 2-comma club etc.

https://jsfiddle.net/cau40vmk/1/