Fortunately, fierce competition in the mutual fund industry generally keeps loads well below this legal maximum. Back-End Loads are also fees used to pay for the marketing of fund shares. Rather than paying the sales load up front, however, with back end loads, the fees are deducted as money is withdrawn. This fee is similar in purpose to a load, in that it's used to pay sales commissions and marketing expenses. However, instead of charging for these through a direct load, 12b-1 fees are deducted from investment performance.
All funds including no-load mutual funds have management and other fees.
These fees are used to pay the professional money managers for their work investing the fund's money. Rather than bill you for these fees, most funds simply reduce the investment return of the fund to pay management fees. The law requires that these fees be clearly spelled out near the front of each fund's prospectus. All you have to do is open the prospectus and you'll find the fees fully disclosed. They are appealling because they don't carry the Front, Back, or CDS load charges.