When the check arrives

For context, I'm a heterosexual female. Throughout the course of my dating life, I've experienced this awkward moment so many times:

My date and I have just finished our meal/drinks, and the waiter drops off one check for us that has both our expenses on it. I don't want to make him pay for me. But I also don't want to pay for him. I could suggest splitting it, but a lot of the time one person's order was much more expensive than the other's, so that's not ideal.

The solution I usually go with is to ask the waiter for separate checks. This feels awkward because it's like I'm saying, "I don't want to pay for my date."

You know how all this could be avoided? If waiters brought separate checks to begin with! Then there'd be no awkwardness. If one person wants to treat the other, he or she could ask for one check with both parties' expenses. This isn't nearly as awkward as asking for separate checks because the former action demonstrates generosity, whereas the latter demonstrates stinginess.

So, why don't waiters bring out separate checks by default?