Well think about it this way... if you're using disposable napkins, that's at least $4 on a package, and that only lasts for a little while ... it's a recurring cost rather than a one-time cost.
I bought a set of reusable cloth napkins on etsy for like $15, hand-stitched linens that someone had bought used and wanted to pass on. This may seem expensive in the short term, $15 for 6, as opposed to $3 for a cheap huge pack. But in the long run, it will save a ton of money, as well as save all that paper and other resources from being used to make disposable napkins.
Cloth is always worth it. 
Just please please please don't buy mass-manufactured, and especially not from Target. Do you really want to use something every day knowing that kids or poor women stitched them together for low wages, working back-breakingly long hours, at sweatshops overseas..??
