I've been a member of SCBWI Canada East Chapter for almost 20yrs now (and was the Illustrator Co-ordinator of the chapter) . Joining does NOT help directly in getting published, nor in attracting an Agent but indirectly is a different story. The industry can be very isolating and what I have found is, the personal friends you make with your peers, via the in person chapter conferences (and on line) can sometimes mean the difference from throwing up your hands and quieting the insanity of trying to create a career in the field or carrying on. No one will understand rejection, acceptance, and the tiny accomplishments in between the two, more then others going through it.
Now, you don't have to be a member to attend the Conferences BUT the difference in cost between member and non, is roughly the annual membership fee.
Now there are always the FEW exceptions, stories of a new writer having an Editor or Agent critique and then getting signed afterwards. BUT those are the exceptions. Don't ever join or attend a conference (or pay extra for the critiques) with that assumption of being "discovered" in mind because that's not what going is about and you'll be terribly disappointed. Again, you go to learn!
The Conferences feature the BEST of the industries Agents, Editors, Authors and Illustrators on faculty and open, for a few months after attending, a window to submit your manuscript to the various houses typically closed to unagented Authors. But that's does NOT mean you will always hear back, nor get published. All of that hinges on your work. Still meeting face to face, making connections, getting to talk one on one with an Agent or Editor during breaks or lunch, certainly doesn't hurt.
I don't want to invest my money into something if it doesn't exactly make getting published easier.
There are people who invest 20K and more in a University education, with NO guarantee it will "get them a job" in that field. You can't "buy" a career but you can do everything possible to learn how that industry works (how it doesn't work) and making your craft the best it can be. THAT will improve your chances to be Published.
Check out your regions chapter on line. See what is being offered in the way of local meet ups (which are typically open to anyone the first few times and free) and go check it out