Yes, but when there are no pets around, or humans. You can have a flea infestation even if you don't have pets. Fleas, that just reached maturity, are just waiting for something to jump on to. You can walk near grass, an infested carpet, etc. and they will jump without you noticing. Then, they'll reach your home, and feed off of you, in case you don't have pets. If you have pets, it is a MUST, to comb them every day, and if they play with other dogs, then you need to comb them two or three times a day. Once you see a flea inside your house, you better start spraying something like Raid anti-fleas.
I could not tell.. just a poorly presented vid to me.. didn't even mention what they're dipping the comb in to kill them, if, indeed, there are fleas in that mix.
Fleas DO live in the home, and more importantly, they can stay dormant until they are agitated. Only a small percentage live on the animal. Not sure what the point of this video was