EA could allow people to sell their mods via Origin, with EA taking a portion of every sale. As long as EA can restrict mods so that they have to be downloaded from EA, this would allow community modding while ensuring that EA makes money from allowing modding.
EA aren't that bad if any company restricted mods to be charged which to me is extremely ludacris they'd know its likely to harm sales... So far Simcity's online connection seems okish, its not always-on which was misunderstood from the sensationalist websites such as VG247 or Eurogamer.
Quoted from Wikipedia,