Our usual response is that many of these excursions can be done independently for far less money (and allowing for far greater freedom). But in some cases one does need local help-- the major sites are difficult to get to from the port or the most interesting activities require a guide (dog sledding in Alaska, perhaps or scuba diving in the Caribbean).
In those cases, one has several options. The first is to simply pick up a good guidebook, look up local tour operators and make your own arrangements. This will likely be the most cost effective option.
Or you can employ a company that specializes in creating unique, intimate and often cheaper shore excursions. I know of three that do this: Port Compass (www.portcompass.com), Shore Trips (www.shoretrips.com) and Port Promotions (www.portpromotions.com). These companies offer excursions accommodating a dozen people or less (as opposed to the 40-people-in-a-motorcoach excursions the cruiselines tend to offer); and because their groups are smaller, they often have time to fit in more adventures in a day, since time isn't wasted shepherding large crowds of travelers.
|Snorkeling with sting rays is a popular shore excursion in Grand Cayman|
Will one save money with these companies? The answer is yes, definitely, if you're traveling with a group of six or more people. In those cases, the per person cost will be far less than what the cruise line is charging.
When couples book these trips, the savings can be negligible. A lot will depend on how many other cruisers also bite (the more who book, the lower the cost for each).
But even with higher costs (which tend to equal rather than surpass the cruiseline's prices in those cases when these tours don't save travelers money) these sorts of shore excursions may be the better experience, for the reasons enumerated above.
The only reason NOT to go it alone, or use an outside community? If you don't own a watch.
With the cruiseline-sponsored shore excursions the ship will wait if the bus is delayed getting back to port. No such courtesy is extended to those who go it on their own. Still, for sensible folks with a good sense of timing, this shouldn't be too much of an issue.