People who issue alts in 2013 have five years of bitcoin experience to go on - they know that miners will jump on it, to try to get in early and make some money.
Back in 2009, nobody knew. Nobody even knew if the cryptography was sound and it would really eliminate double spending, let alone that it would take off the way it did and be actually worth something. The early guys were not really miners, they were cryptography geeks and mathematicians bent on solving the digital problem of how to move money online securely, and on testing it and building the infrastructure (eg I understand Hal Finney did quite a lot of work on coding the wallet).
They were scientists and pioneers. It really wasn't about pre-mining and making a killing - that's the mindset of the non-scientists who came afterwards and piggy backed on the original idea (even issuing alts because Satoshi kindly make his code open source so they could copy it!).