Carol is right that very few mass market cruise ships would be in port for a long enough time that would make taking the Tiko Tiko practical - even if theoretically possible. All of the Tiko trips are 9 to 5, I think - do not remember for sure. When you consider that to make it a comfortable excursion off a ship time-wise you would have to have at least a scheduled ship arrival time by 8 am and a scheduled ship departure time of 6:00 pm or later, there are few mass market cruise ships that are in port that long.
We are cruisers who also do land vacations in SXM. Our experience is that if there is someone making people at CO (or Baige Rouge or Happy Bay or whereever) uncomfortable with "gawking" or other obnoxious activity, it is someone who is on the island longer than a port of call stop - it is not a cruiser (someone off a cruise ship on a port of call). I do not think I have ever seen someone that I thought or knew was a cruiser be an obnoxious "gawker" - not to say there are not some. A lot of cruisers have never been to CO before and are understandably curious about it and unsure of how to act - I think in general the "regulars" are welcoming of the normal cruiser.