Absolutely. I honestly don't take offers seriously from people who haven't even seen what you're selling in the flesh - I might be wrong, it's almost always people looking to flip what you're selling for profit as opposed to someone looking for the best for what they can budget for.
I haven't previously thought much about the psychology of it, but It takes longer for genuine buyers to find what you're selling because they have a lot of ground to cover with regards to ensuring the vehicle isn't a rotbox, stolen, dangerous, poorly maintained etc.
Chancers & flippers actively look for things to low-ball - for them, it's a numbers game, the more low-ball offers they get out in a day the more chance of hooking a desperate sucker there is. Would I being a lazy stereotyper to allude than maybe these kind of folks don't have a regular paying vocation? (i.e. a job)
That's maybe why there seems to be more arseholes offering peanuts for your car than genuine sellers.