Whatever genie is making this deal with me still has a lot of room for interpretation!
The biggest question remains: can you relearn, or are you selling away your ability to ever be good at this thing? Because if you can sit down and work hard and relearn art, and you're relatively young.... I'm with @efdvorsky, I could see that really being worth it for some artists!
(sidebar: heck, you could have an entire business model built on that -- study and work for years to become good at a thing and then sell your ability to be good at that thing for a huge amount of money, and then just study again until your talent is big enough for another sale? There's definitely a sci-fi story premise hiding in this scenario,,,,,)
If you make comics as your main passion, "anything that feeds into your main passion" includes storytelling, communication (which would affect your ability to communicate well outside of comics), creativity, an eye for aesthetics (you need to be able to tell when your drawings look good and when they don't), the ability to choose colours well (all of which would affect any graphic design abilities as well as having repercussions on your ability to present yourself well), and an ability to draw. How about your ability to sell yourself and your work? Your ability to network with others? Those are important all over the place in life, but they tie into webcomicking too; are they included?
Or is this a magic bargain where you keep those abilities outside of comics but just whenever you sit down to draw a comic something magically prevents any of it from working?