Of course, we know that there's nothing in the venom of the hobo spider that is more dangerous than other garden-variety spiders; that has been proven several times, most recently by WSU.
Further, most of the spiders identified as hobos are actually mis-identified. Here's the best guide on how to not mis-identify a hobo spider.
So is the hobo a "safe" spider? Look at it this way--we're learning more about allergies and proteins all the time, and it may be that some people will react to certain amino acids that others will not. Bee stings are the perfect example of this.
How do you tell if it's a hobo? I refer you back to the guide. Here's a hint: get out your scope, because you can't tell with the naked eye. A super-duty magnifying glass may work, but a low-powered microscope is best. Here's a question, though: Now that you know it's NOT especially dangerous, do you really care whether it's Tegenaria agrestis, Tegenaria gigantea/duellica, or Tegenaria domestica?
While not especially dangerous, nobody wants a spider to bite him or her. For that matter, you don't want anything biting you, whether it's a 3-year-old or a tiger! One of the big reasons is infection, and that's what the early hobo bites proved to be--infected puncture wounds that resulted after the patient rubbed bacteria into a hobo bite wound.
Can you treat for hobo spiders? Yes, but don't expect a bomb to work. They don't leave any residual.
For the record, I have sent an email to Victor, who made the "pre-baited" trap shown above. I'll let you know as soon as I found out what it is they're using for bait!
Picture shown below was taken by Chris, on our staff. It's a female hobo spider.