The Epic First Run programme allows developers of any size to claim 100% of revenue if they agree to make their game exclusive on the Epic Games Store for six months.
After the six months are up, the game will revert to the standard Epic Games Store revenue split of 88% for the developer and 12% for Epic Games.
The alternative was to not use a launcher, which is what most people wanted at the time. Gabe even came out and said, after the Steam launch of Half-Life 2, that the Steam situation was bad. Some reviews of HL2 went as far as to deduct points from their reviews based on the fact that Steam made the experience of playing the game worse than it would have been if you could have just installed and played the game without a launcher.
Also, there was a launcher that predated Steam and was more mature and polished than Steam at the time. It was Stardock’s Stardock Central, which came out in 2001(about three years before Steam) and began offering third party games for sale in 2004.