I know it's conventional wisdom that the guy should pay on the first date, but I disagree - I think it should be split 50/50. That being said, I can't find a single guy or girl who agrees with me. Speaking from a logical, feminist, 21st century perspective, aren't I right?
From a logical, practical (and yes, feminist) standpoint, you're totally right. Unfortunately, like everyone else you've already asked, I'm still going to advocate that the guy pays on the first date. Also, before I go any further, I want to be clear about the fact that the question was asked from a heterosexual perspective, so that's how I'm addressing it, while fully admitting my ignorance here about how the bill gets decided on same-sex dates.
If you're a guy who wrote this question and you suggest splitting the bill on an actual date, the girl is probably going to see "cheap" written all over your forehead, which doesn't usually translate into a second date. If you're a girl, then by all means offer to split the bill, but if the guy takes you up on it, I really do hate to say this, but I think you've learned something about his true character.
I have heard the flip side, too, though, which is that if a girl doesn't at least reach for her wallet, she can come across as cheap and entitled, and the guy starts to worry about his own bank account as well as her character. As a general rule, it makes sense for the person who initiates the date to pay. The vast majority of the time, guys are the ones doing the asking, particularly for first dates, which translates into guys doing the paying. (For my thoughts on women doing the asking out, check out this post.)
I think it's totally appropriate for a girl to say at the end of the first date, after the guy has declined her offer to split the bill, "Thanks so much for dinner. I look forward to treating next time." Then the expectation has been set and the couple doesn't have to do the awkward "wallet dance" every time. It also makes sense that the person who chooses the location pays, since a guy (or girl) might suggest a restaurant or activity out of the other's price range. This also means that, guys, don't suggest a place for the first date that you can't afford, since you should go into it expecting to foot the bill. And girls, this means you shouldn't order the most expensive thing on the menu. Again, the flip side is that, guys, you shouldn't suggest the rundown pizza joint around the corner just to save a few bucks, and girls, you also shouldn't suggest an expensive place expecting the guy to pay.
I know that dating can get expensive, and I know that that burden really is placed unfairly on guys. That's one of the reasons I suggest inexpensive (as well as less time-intensive) first dates. Go for coffee instead of brunch or drinks instead of dinner. Find out how much you want to invest in the person, both in terms of time and money, before you splurge on the five-course tasting menu.
If you do find someone who sees eye to eye with you on this issue, then maybe that's a sign, and you're meant to be together. In the meantime, approach this social convention as a historical relic that simplifies the end of the date and gives both parties a chance to look good.