There really isn't a reason for me. For the most part, I don't spend that much money on non-tangibles. One could argue that $20 isn't that much but one of the reasons that my finances continue to be in such great shape despite life's occasional curveball is that I sweat the small stuff. You spend $20 here and there and that stuff adds up by the end of the year.
Even going beyond the money and the non-tangible reasons, I just looked at the benefits and they are all useless.
HD video: To paraphrase Yahtzee, I'm not going to think these videos are better if there is a 20% jump in resolution.
Podcasts and RSS feeds: Who cares?
Get a backstage look at The Escapist's production pipeline, including outtakes, behind-the-scenes, sneak previews, drafts, and members-only contests. : Don't care about the nuts and bolts of how they do it.
A custom title: I don't care about my title now.
Early access to upcoming site features: So I can pay to be a Beta tester?
Ad-Free: Meh. Some of the ads are amusing.
Shipping Discounts from SCIFIGENRE: I don't buy anything there.
A discount at Edges of Reality: I actually have two FULLY SHARPENED blades. I have no need for a replica sword that would be dull and useless in an actual panic situation.
Discount for New York Comiccon: Wouldn't go anyway.
Automatic Contest Entries: I don't bother entering the contests now.
Exclusive Member forum: So? Most of those people probably come out here now. Plus, while Gamefaqs may not be a good indicator of this, I find that most people in exclusive forums can be territorial wankers.
Ability to be part of a focus group and fill out surveys on the site's direction: Nothing that I would participate in.
In the end, I come here to watch the video and use the forums. If they put out a T-Shirt that I like, I may support them that way. But, even if I did spend money on intangibles, none of this would really entice me to join. I'm not saying all this to troll but that's just how I feel about it.