Merengue dutchie,
I agree completely with every point you make.
However, this does not mean that people do not misconstrue, misjudge, and use completely subjective guesses with their eyes, tastes, and assessments. Again, since i hear this subject guesses and assessments everyday, i will just point a few out of them that make me question people's power of observtion skills. Here is something that happens every single day, in every single restaurant, all around the world.
1. "My drink is weaker than normal." We get this complaint everyday despite the fact that in the restaurant where i work--both in Cabarete and here in Norway--all drinks get measured. every single pour is measured. Here in Norway, every drink gets about 1 ounce (4cl) of alcohol--it is measured by law, and in Cabarete every drink gets 1.5 ounces (where i work) unless it is something like a "Tall drink"--i.e-LOng Island Ice Tea--these get much more alcohol. And yet, Despite everyone being aware of this, people, everyday, complain about their drink being weaker than normal. This dumbfounds me. Every drink is measured, and when i point this out, people seem to disbelieve it even when they are sitting at the bar watching me make the drink!
In the DR and USA, i wish i had a dollar everytime someone said this: "This is not Absolut vodka," or "Grey Goose", or "Bacardi," (subsitute whatever alcohol you like). I'm like, but wait, you just saw me pour the f^&*king drink! What else can it be? Waiters constantly come back to the bar and say "This person claims that their absolut cranberry or absolut tonic (substitute whatever liquor here you want here) is not Absolut." People send glasses of wine back constantly claiming that the wine is "Corked." Again, we serve no wine in the DR that even uses a "Cork!" So, again, people are using subjective tastes.
2. People will complain that their Grouper, Salmon, Trout, etc. is not the same size as previous. Ok, this probably the case, and often, this is a statement of fact, because, well, let's face it, it's impossible to pull out the exact same size fish, lobster, or crab out of the freezer or fish tank every single time someone orders it--especially if its a very high volume restaurant where they are serving hundreds of lobsters, crabs, or fish a night.
This is where i think its very possible that the OP correctly noticed the serving of lobster being less than normal, he perhaps did not give the benefit of doubt to the restaurant where its very hard to be consistent with serving sizes of lobster and fish. And if in fact, the owner told him on a previous occassion when he complained that the servings are the same and nothing has changed, then i have to assume that this is a correct statement and that sometimes you get slightly more, and sometimes slightly less, since they are probably like any other DR restaurant--not exactly fastidious to serving weight and details.
Frank