They can if they want to waste there time and money. But I can just not beat around the bush and write, "I have sex for money." Which word will they get rid of or search for; 'I' 'have' 'sex' 'for' or 'money.'
These sites have less to worry about because it's a bunch of varied accounts. Someone can fine their account and ask for it to be removed, but it'll have to be done one by one.
Anyway, if they're going to spend money to search and remove account, they should start with Russian Bots not escorts.