I thought I would make a list to show you what the benefits are for using acrylic instead of cotton yarn to make a wash/dish cloths:
3. dries quicker
4. last longer
5. takes longer to get moldy smelling*
Now in Japan, they even make a yarn that is antibacterial. They use it to make what they call tawashi or in other words a cute scrubber. You can buy the yarn here from ichigonopantsu's etsy shop. I'm sure there are other places that sell this yarn but that's the only place I know of right now.
*easily fixed by regular trips through the washing machine or pop it into the dishwasher with your dirty dishes.