I feel that the neck pulse can have a clinical significance. What you are seeing, however, is most likely just simple variations in the structure of each individual. People with thinner musculature, etc. in the neck may have more apparent pulsing than others with more musculature.
The neck pulse is an easy place to see a bounding pulse, however, so if people are nervous, have anxiety, have thyroid conditions, blood pressure issues, nerve issues in the neck, etc. you will see some of the activity here - but you will almost always feel that within the traditional wrist pulses and see it in other diagnostic methods.
Within the Tam Healing System that I primarily use we focus quite a bit in that area (i.e. the sky window points), but we rely more on palpatory pressure pain at the points rather than any clinical significance of the pulse in that area.
Historically there were a range of positions that were used within pulse diagnosis outside of the wrist - the neck, the ankles, etc. Some of these techniques are no longer used and generally this happens by the indications from the area not being more clinically significant than the information derived from other methods.