That sentence make me confused cause, well yes you are selling cash shop items for gils thus, it is RMT as stated by the definition BUT you don't get any real money, it all goes to SE and that's why, imho, Trion did not do anything regarding this, cause in the end, they are the winner, getting money they would not have get otherwise cause the item would not have spend real money in the CS.
The person who is selling is converting cash into gil and the person buying is converting gil into cash(albeit an item that is bought for gil instead of real money) so yes it is real money trading.