Registrars are still allowed to add a markup, just there is so much competition that doesn't really happen any more.
EDIT: Correction, Network Solution was the _only_ registrar between 1995 and 1998. For three years they charged insane amounts, $100 for 2yrs. Before that it was free, and after that it was about $8 from other registrars.
[EDIT] I must have paid for two years (maybe first time registrations had to be two years, at the time?) at a $34.99/yr rate, to get that $70 figure I had in my head, in 2002.
[1] https://web.archive.org/web/20000510064309/http://www.direct...
I don't remember the exact year from handoff from NetSol to ICANN approved registars, but some of that work started in September 1998. I found some sources that state sometime during 2001 was when NetSol had it's exclusive registrar service ended.