I just heard that old wives tale about how many spiders you eat in your lifetime. It's supposed to be something like 15 spiders or maybe 20. I think it's bunk. I happen to know, from experience, that just because a spider crawls on you in the middle of the night, it's not going to accidentally end up in your mouth. It's going to crawl on your arm. And if you have stitches that poke out, it's going to snuggle right in there and hide when you wipe your hand over your arm in the middle of the night.
But the second time you feel that tickle, you will not miss the spider and will throw it against the wall with an audible (albeit small) thud. So you see, the spider will not even make it into your mouth!
The other dumb part of that tale is that even if it did crawl into your mouth, it's not going to crawl down your throat to its death. I think you would choke first, but the spider would figure out it's in the wrong spot and crawl back out of your mouth again. You wouldn't know, you're sleeping. Kind of like when a spider ends up on a trampoline and it doesn't like all the bouncing and screaming when a couple of girls discover that it's there. The spider high-tails it out of there. And fast, too, if the girls are screaming to their mom to "Smash it!" while handing her a metal water bottle.
I've seen enough spiders to know that they will do what they can for self-preservation just as any human would do, too. ("I did not have sexual relations with that woman.") And staying alive is high on the priority list. In fact, spiders can be just as tenacious about getting what they want as any small child who becomes skilled at nagging desired behavior out of their mom. We have several orb spiders building giant webs in the pathway to our front door this summer. No matter how many times I knock down the web before running into it face first, they insist upon rebuilding in the same spot - though, to their credit, they go higher each time and now they're nearly overhead.
But that eating spiders because they end up in our mouths, that's dumb. And since I'm nearly an old wife, you can believe my tales now.