"...why you would need to do it in the first place, it's fine as is."
Wax serves two purposes on a bowstring--waterproofing and lubrication. Since modern materials are not affected by moisture like sinew and such, lubrication/maintenence is the primary reason you wax your string.
Bowstring material is made up of lots of little fibers. When you shoot, these fibers rub against each other and break--that's why strings fuzz up. To get the best protection against this, you need a wax that will penetrate into the string, not just coat the outside. Straight bee's wax is too hard, unless you melt it (whole 'nother set of problems there). Mixing it with another compatable material softens it so it's easier to get it down into the fibers.
Materials like BCY's 8125G and the new 8190 incorporate GORE fiber in the material. It's similar to Teflon, and helps lubricate the string--that's why these materials fuzz up less.
Chad