With font purchasing from sites like Blambot and Comicraft, once you pay for the font you're pretty much buying a license to use it however you need(with certain limits), so the licensing works for you being an comic creator if you're using the fonts for lettering comics and/or logo design. I letter my comics with their fonts and print my comics; there are freelance letterers who use their fonts to letter books for mainstream companies(like Marvel & DC)- as long as those letterers dont give a copy of their fonts to Marvel/DC, they are good.
They want & encourage small indie comic creators to buy their fonts to use for their comics- that's the purpose of these sales. Comicraft is a little more expensive than Blambot, but they both offer sales- or in Blambot's case- free fonts for creators to use to make comics.
I started out buying like one or 2 every sale until I started making enough to buy more; I would pick the one(s) that I felt I REALLY NEEDED- which were mostly/mainly sound FX fonts.