To the first question, absolutely! Open up your best hot dog stand, Sans.

The goblins are, frankly put, kind of morons. They might see Sans, see a femur and immediately think something along the lines of, "Club! Weapon!" They would back off after a first encounter though, after realizing that Sans' bones are not actually a potential weapon that they can just grab and leave with.

The dwarves would be largely indifferent. They've Seen Some Shit.