this number is incorrect , or you get fooled, I was working in a startup that was exactly helping people creating companies with the paperwork, including the step you're mentionning, and it was 20 to 30 euros , maybe 50 depending on the journal and option you take

200~300 euros was the price we billed for a startup creation including ALL the paperwork, admnistrative fee, publication fee, and the fact we will review all your documents before submiting them to the french administration and do the follow up with you in case your submission was still denied.