Shops can agree on a benchmark price, but are, of course, always free to vary from it when push comes to shove. Mermaid's, for example, agreed to bump day trip prices last November after the 3 biggest shops all agreed to it. They never actually did it, however. They're price is still what it was pre-October. In fact, new ownership there has their new beach road shop selling snorkelers at 2005 prices and dive trips at 2500 because they're just a block away from the old Mermaid's shop.
No one wins on severe price competition. Sure, the customer may get a break short term, but eventually service and quality suffer. There are plenty of examples of that in Thailand where ther'es an oversupply of shops who are willing to go to any price for, say, open water courses. If you're doing OWs for 7,000 baht, corners will need to be cut.
It's not good for the shop, the industry and ultimately the customer.
OW courses in Pattaya, btw, have been the same price for more than 6 years, at 14000 baht. A couple shops do it for less, or include the manual for that price, but most stick to the benchmark and instead try to market based on the size/quality of the boat, the meal & hotel pickiup service, the amount and quality of the gear and the standard of the instrucors and DMs.
As it should be, imho.
