I think at the end of the day, you don't know what tomorrows going to bring. You may be getting job offers now, but what does that really get you? Not sure if you're in the US or not, but at least in the US, Employment is at-will in many states,
especially for engineers.
In many, many, many cases, I think a degree cannot hurt you, only help you. Yes, I have seen examples of people who would rather work with someone without a degree, but I truly believe those employers are few and far between. If you ever get tired of living the start-up life (you never know what tomorrow brings, what if you start a family and don't want the risks associated with freelancing? What if you just decide one day it's not for you anymore? The only thing certain about the future is that it's uncertain), a degree will get you in the door at places that offer A) Great Pensions/Retirement packages, B) Great Healthcare, and other great perks, places that you probably wouldn't even get an interview if you don't have your degree.
Personally speaking, I have a great deal of respect for anyone who knows what they're doing. I've worked with people without a formal education, and those with. There's a major difference though, in that the people I've worked with who have a formal education, we have common ground. Meaning, it's much more likely that when I say the "pigeon hole principal", someone who took discrete mathematics (one of the cornerstones of CS) will remember something about it. For someone without a degree, there's a lower chance that they'd know what I was talking about (not impossible, not unlikely even, just less of a chance).
Does that matter? Not a whole lot for some stuff, but in other areas absolutely. In software, I generally am not disappointed if my colleagues haven't designed something using an FPGA and Verilog, or have any clue as to the difference between x86 and x64 ISAs, but if they don't get the concept of a linked-list, or a queue, stack, or something else fundamental to computer-science, it does slow work down. If they're a javascript developer and don't know what a prototype is, or how function literals/closures work, it can slow communication down.
Then again, I haven't worked much in the front-end, or even in Web. I focus primarily on desktop/server/batch/financial software, so I work in low level code, such as c/c++/COBOL and Java(debatably high-level).
At it's core, engineering is the use of knowledge and the scientific method to solve problems and build cool/useful stuff. Experience builds that knowledge, and all college does is focus your experience on knowledge that a group of people believe will be useful to you, as well as on a meta-level as well (learning how to learn was really what I took away from school the most).
Just keep in mind that going back is way harder than just finishing it while you're already there. You get use to the perks of being at work, and then going back to the academic life really gets harder, the longer your away (at least that's what I've found).
Hope that helps, and good luck on your journey.